From Wikipedia, the free encyclopedia
Internet users per 100 population members and GDP per capita for selected countries.
The
Internet (
contraction of
interconnected network) is the global system of interconnected
computer networks that use the
Internet protocol suite (TCP/IP) to link devices worldwide. It is a
network of networks
that consists of private, public, academic, business, and government
networks of local to global scope, linked by a broad array of
electronic, wireless, and optical networking technologies. The Internet
carries a vast range of information resources and services, such as the
inter-linked
hypertext documents and
applications of the
World Wide Web (WWW),
electronic mail,
telephony, and
file sharing.
The origins of the Internet date back to research commissioned by the
federal government of the United States in the 1960s to build robust, fault-tolerant communication with computer networks. The primary precursor network, the
ARPANET,
initially served as a backbone for interconnection of regional academic
and military networks in the 1980s. The funding of the
National Science Foundation Network
as a new backbone in the 1980s, as well as private funding for other
commercial extensions, led to worldwide participation in the development
of new networking technologies, and the merger of many networks.
The linking of commercial networks and enterprises by the early 1990s
marked the beginning of the transition to the modern Internet, and generated a sustained exponential growth as generations of institutional,
personal, and
mobile computers were connected to the network. Although the Internet was widely used by
academia since the 1980s,
commercialization incorporated its services and technologies into virtually every aspect of modern life.
Most traditional communications media, including telephony,
radio, television, paper mail and newspapers are reshaped, redefined, or
even bypassed by the Internet, giving birth to new services such as
email,
Internet telephony,
Internet television,
online music, digital newspapers, and
video streaming websites. Newspaper, book, and other print publishing are adapting to
website technology, or are reshaped into
blogging,
web feeds and online
news aggregators. The Internet has enabled and accelerated new forms of personal interactions through
instant messaging,
Internet forums, and
social networking.
Online shopping has grown exponentially both for major retailers and
small businesses and
entrepreneurs, as it enables firms to extend their "
brick and mortar" presence to serve a larger market or even
sell goods and services entirely online.
Business-to-business and
financial services on the Internet affect
supply chains across entire industries.
Terminology
When the term
Internet is used to refer to the specific global system of interconnected
Internet Protocol (IP) networks, the word is a
proper noun that should be written with an initial
capital letter. In common use and the media, it is often erroneously not capitalized, viz.
the internet. Some guides specify that the word should be capitalized when used as a noun, but not capitalized when used as an adjective. The Internet is also often referred to as
the Net, as a short form of
network. Historically, as early as 1849, the word
internetted was used uncapitalized as an adjective, meaning
interconnected or
interwoven. The designers of early computer networks used
internet both as a noun and as a verb in shorthand form of
internetwork or internetworking, meaning interconnecting computer networks.
The terms
Internet and
World Wide Web are often used interchangeably in everyday speech; it is common to speak of "
going on the Internet" when using a
web browser to view
web pages. However, the
World Wide Web or
the Web is only one of a large number of Internet services. The Web is a collection of interconnected documents (web pages) and other
web resources, linked by
hyperlinks and
URLs. As another point of comparison,
Hypertext Transfer Protocol,
or HTTP, is the language used on the Web for information transfer, yet
it is just one of many languages or protocols that can be used for
communication on the Internet. The term
Interweb is a
portmanteau of
Internet and
World Wide Web typically used sarcastically to parody a technically unsavvy user.
History
Research into
packet switching, one of the fundamental Internet technologies started in the early 1960s in the work of
Paul Baran, and packet switched networks such as the
NPL network by
Donald Davies,
ARPANET,
Tymnet, the
Merit Network,
Telenet, and
CYCLADES, were developed in the late 1960s and 1970s using a variety of
protocols. The ARPANET project led to the development of protocols for
internetworking, by which multiple separate networks could be joined into a network of networks. ARPANET development began with two network nodes which were interconnected between the Network Measurement Center at the
University of California, Los Angeles (UCLA)
Henry Samueli School of Engineering and Applied Science directed by
Leonard Kleinrock, and the NLS system at
SRI International (SRI) by
Douglas Engelbart in
Menlo Park, California, on 29 October 1969. The third site was the Culler-Fried Interactive Mathematics Center at the
University of California, Santa Barbara, followed by the
University of Utah Graphics Department. In an early sign of future growth, fifteen sites were connected to the young ARPANET by the end of 1971. These early years were documented in the 1972 film
Computer Networks: The Heralds of Resource Sharing.
Early international collaborations on the ARPANET were rare. European developers were concerned with developing the
X.25 networks. Notable exceptions were the Norwegian Seismic Array (
NORSAR) in June 1973, followed in 1973 by Sweden with satellite links to the
Tanum Earth Station and
Peter T. Kirstein's research group in the United Kingdom, initially at the
Institute of Computer Science,
University of London and later at
University College London. In December 1974,
RFC 675 (
Specification of Internet Transmission Control Program), by
Vinton Cerf, Yogen Dalal, and Carl Sunshine, used the term
internet as a shorthand for
internetworking and later
RFCs repeated this use. Access to the ARPANET was expanded in 1981 when the
National Science Foundation (NSF) funded the
Computer Science Network (CSNET). In 1982, the
Internet Protocol Suite (TCP/IP) was standardized, which permitted worldwide proliferation of interconnected networks.
T3 NSFNET Backbone, c. 1992.
TCP/IP network access expanded again in 1986 when the
National Science Foundation Network (NSFNet) provided access to
supercomputer sites in the United States for researchers, first at speeds of 56 kbit/s and later at 1.5 Mbit/s and 45 Mbit/s. Commercial
Internet service providers (ISPs) emerged in the late 1980s and early 1990s. The ARPANET was decommissioned in 1990.
Stanford Federal Credit Union was the first
financial institution to offer online internet banking services to all of its members in October 1994. In 1996
OP Financial Group, also a
cooperative bank, became the second online bank in the world and the first in Europe.
By 1995, the Internet was fully commercialized in the U.S. when the
NSFNet was decommissioned, removing the last restrictions on use of the
Internet to carry commercial traffic. The Internet rapidly expanded in Europe and Australia in the mid to late 1980s and to Asia in the late 1980s and early 1990s. The beginning of dedicated
transatlantic communication between the NSFNET and networks in Europe was established with a low-speed satellite relay between
Princeton University and
Stockholm, Sweden in December 1988. Although other network protocols such as
UUCP had global reach well before this time, this marked the beginning of the Internet as an intercontinental network.
Public commercial use of the Internet began in mid-1989 with the connection of MCI Mail and
Compuserve's email capabilities to the 500,000 users of the Internet.
Just months later on 1 January 1990, PSInet launched an alternate
Internet backbone for commercial use; one of the networks that would
grow into the commercial Internet we know today. In March 1990, the
first high-speed T1 (1.5 Mbit/s) link between the NSFNET and Europe was
installed between
Cornell University and
CERN, allowing much more robust communications than were capable with satellites. Six months later
Tim Berners-Lee would begin writing
WorldWideWeb, the first
web browser
after two years of lobbying CERN management. By Christmas 1990,
Berners-Lee had built all the tools necessary for a working Web: the
HyperText Transfer Protocol (HTTP) 0.9, the
HyperText Markup Language (HTML), the first Web browser (which was also a
HTML editor and could access
Usenet newsgroups and
FTP files), the first HTTP
server software (later known as
CERN httpd), the first
web server, and the first Web pages that described the project itself. In 1991 the
Commercial Internet eXchange
was founded, allowing PSInet to communicate with the other commercial
networks CERFnet and Alternet. Since 1995 the Internet has tremendously
impacted culture and commerce, including the rise of near instant
communication by email,
instant messaging, telephony (
Voice over Internet Protocol or VoIP),
two-way interactive video calls, and the
World Wide Web with its
discussion forums, blogs,
social networking, and
online shopping
sites. Increasing amounts of data are transmitted at higher and higher
speeds over fiber optic networks operating at 1-Gbit/s, 10-Gbit/s, or
more.
The Internet continues to grow, driven by ever greater amounts of online information and knowledge, commerce, entertainment and
social networking.
During the late 1990s, it was estimated that traffic on the public
Internet grew by 100 percent per year, while the mean annual growth in
the number of Internet users was thought to be between 20% and 50%.
This growth is often attributed to the lack of central administration,
which allows organic growth of the network, as well as the
non-proprietary nature of the Internet protocols, which encourages
vendor interoperability and prevents any one company from exerting too
much control over the network. As of 31 March 2011, the estimated total number of
Internet users was 2.095 billion (30.2% of world population). It is estimated that in 1993 the Internet carried only 1% of the information flowing through two-way
telecommunication,
by 2000 this figure had grown to 51%, and by 2007 more than 97% of all
telecommunicated information was carried over the Internet.
Governance
The Internet is a
global network
that comprises many voluntarily interconnected autonomous networks. It
operates without a central governing body. The technical underpinning
and standardization of the core protocols (
IPv4 and
IPv6) is an activity of the
Internet Engineering Task Force
(IETF), a non-profit organization of loosely affiliated international
participants that anyone may associate with by contributing technical
expertise. To maintain interoperability, the principal
name spaces of the Internet are administered by the
Internet Corporation for Assigned Names and Numbers
(ICANN). ICANN is governed by an international board of directors drawn
from across the Internet technical, business, academic, and other
non-commercial communities. ICANN coordinates the assignment of unique
identifiers for use on the Internet, including
domain names,
Internet Protocol (IP) addresses, application port numbers in the
transport protocols, and many other parameters. Globally unified name
spaces are essential for maintaining the global reach of the Internet.
This role of ICANN distinguishes it as perhaps the only central
coordinating body for the global Internet.
The
National Telecommunications and Information Administration, an agency of the
United States Department of Commerce, had final approval over changes to the
DNS root zone until the IANA stewardship transition on 1 October 2016. The
Internet Society (ISOC) was founded in 1992 with a mission to
"assure the open development, evolution and use of the Internet for the benefit of all people throughout the world". Its members include individuals (anyone may join) as well as corporations,
organizations,
governments, and universities. Among other activities ISOC provides an
administrative home for a number of less formally organized groups that
are involved in developing and managing the Internet, including: the
Internet Engineering Task Force (IETF),
Internet Architecture Board (IAB),
Internet Engineering Steering Group (IESG),
Internet Research Task Force (IRTF), and
Internet Research Steering Group (IRSG). On 16 November 2005, the United Nations-sponsored
World Summit on the Information Society in
Tunis established the
Internet Governance Forum (IGF) to discuss Internet-related issues.
Infrastructure
2007 map showing submarine fiber optic telecommunication cables around the world.
The communications infrastructure of the Internet consists of its
hardware components and a system of software layers that control various
aspects of the architecture.
Routing and service tiers
Packet routing across the Internet involves several tiers of Internet service providers.
Internet service providers
(ISPs) establish the worldwide connectivity between individual networks
at various levels of scope. End-users who only access the Internet when
needed to perform a function or obtain information, represent the
bottom of the routing hierarchy. At the top of the routing hierarchy are
the
tier 1 networks, large telecommunication companies that exchange traffic directly with each other via very high speed
fiber optic cables and governed by
peering agreements.
Tier 2 and lower level networks buy
Internet transit
from other providers to reach at least some parties on the global
Internet, though they may also engage in peering. An ISP may use a
single upstream provider for connectivity, or implement
multi-homing to achieve redundancy and load balancing.
Internet exchange points
are major traffic exchanges with physical connections to multiple ISPs.
Large organizations, such as academic institutions, large enterprises,
and governments, may perform the same function as ISPs, engaging in
peering and purchasing transit on behalf of their internal networks.
Research networks tend to interconnect with large sub-networks such as
GEANT,
GLORIAD,
Internet2, and the UK's
national research and education network,
JANET. Both the Internet IP routing structure and hypertext links of the World Wide Web are examples of
scale-free networks. Computers and routers use
routing tables in their operating system to
direct IP packets to the next-hop router or destination. Routing tables are maintained by manual configuration or automatically by
routing protocols. End-nodes typically use a
default route that points toward an ISP providing transit, while ISP routers use the
Border Gateway Protocol to establish the most efficient routing across the complex connections of the global Internet.
An estimated 70 percent of the world's Internet traffic passes through
Ashburn,
Virginia.
Access
Common methods of
Internet access by users include dial-up with a computer
modem via telephone circuits,
broadband over
coaxial cable,
fiber optics or copper wires,
Wi-Fi,
satellite, and
cellular telephone technology (e.g.
3G,
4G). The Internet may often be accessed from computers in libraries and
Internet cafes.
Internet access points exist in many public places such as airport halls and coffee shops. Various terms are used, such as
public Internet kiosk,
public access terminal, and
Web payphone.
Many hotels also have public terminals that are usually fee-based.
These terminals are widely accessed for various usages, such as ticket
booking, bank deposit, or online payment. Wi-Fi provides wireless access
to the Internet via local computer networks.
Hot spots providing such access include
Wi-Fi cafes, where users need to bring their own wireless devices such as a laptop or
PDA. These services may be free to all, free to customers only, or fee-based.
Grassroots efforts have led to
wireless community networks. Commercial Wi-Fi services covering large city areas are in many cities, such as
New York,
London,
Vienna,
Toronto,
San Francisco,
Philadelphia,
Chicago and
Pittsburgh. The Internet can then be accessed from places, such as a park bench. Apart from Wi-Fi, there have been experiments with proprietary mobile wireless networks like
Ricochet, various high-speed data services over cellular phone networks, and fixed wireless services. High-end mobile phones such as
smartphones in general come with Internet access through the phone network. Web browsers such as
Opera
are available on these advanced handsets, which can also run a wide
variety of other Internet software. Internet usage by mobile and tablet
devices exceeded desktop worldwide for the first time in October 2016. An Internet access provider and protocol matrix differentiates the methods used to get online.
Internet and mobile
According to the
International Telecommunication Union
(ITU), by the end of 2017, an estimated 48 per cent of individuals
regularly connect to the internet, up from 34 per cent in 2012.
Mobile internet connectivity has played an important role in expanding access in recent years especially in
Asia and the Pacific and in
Africa.
The number of unique mobile cellular subscriptions increased from 3.89
billion in 2012 to 4.83 billion in 2016, two-thirds of the world's
population, with more than half of subscriptions located in Asia and the
Pacific. The number of subscriptions is predicted to rise to 5.69
billion users in 2020. As of 2016, almost 60 per cent of the world's population had access to a
4G broadband cellular network, up from almost 50 per cent in 2015 and 11 per cent in 2012. The limits that users face on accessing information via mobile applications coincide with a broader process of
fragmentation of the internet. Fragmentation restricts access to media content and tends to affect poorest users the most.
Zero-rating, the practice of
internet providers
allowing users free connectivity to access specific content or
applications for free, has offered some opportunities for individuals to
surmount economic hurdles, but has also been accused by its critics as
creating a 'two-tiered' internet. To address the issues with
zero-rating, an alternative model has emerged in the concept of 'equal
rating' and is being tested in experiments by
Mozilla and
Orange in
Africa.
Equal rating prevents prioritization of one type of content and
zero-rates all content up to a specified data cap. A study published by
Chatham House, 15 out of 19 countries researched in
Latin America
had some kind of hybrid or zero-rated product offered. Some countries
in the region had a handful of plans to choose from (across all mobile
network operators) while others, such as
Colombia, offered as many as 30 pre-paid and 34 post-paid plans.
A study of eight countries in the
Global South
found that zero-rated data plans exist in every country, although there
is a great range in the frequency with which they are offered and
actually used in each. Across the 181 plans examined, 13 per cent were offering zero-rated services. Another study, covering
Ghana,
Kenya,
Nigeria and
South Africa, found
Facebook's Free Basics and
Wikipedia Zero to be the most commonly zero-rated content.
Protocols
While the hardware components in the Internet infrastructure can
often be used to support other software systems, it is the design and
the standardization process of the software that characterizes the
Internet and provides the foundation for its scalability and success.
The responsibility for the architectural design of the Internet software
systems has been assumed by the
Internet Engineering Task Force (IETF).
The IETF conducts standard-setting work groups, open to any individual,
about the various aspects of Internet architecture. Resulting
contributions and standards are published as
Request for Comments
(RFC) documents on the IETF web site. The principal methods of
networking that enable the Internet are contained in specially
designated RFCs that constitute the
Internet Standards.
Other less rigorous documents are simply informative, experimental, or
historical, or document the best current practices (BCP) when
implementing Internet technologies.
The Internet standards describe a framework known as the
Internet protocol suite. This is a model architecture that divides methods into a layered system of protocols, originally documented in
RFC 1122 and
RFC 1123. The layers correspond to the environment or scope in which their services operate. At the top is the
application layer,
space for the application-specific networking methods used in software
applications. For example, a web browser program uses the
client-server application model and a specific protocol of interaction between servers and clients, while many file-sharing systems use a
peer-to-peer paradigm. Below this top layer, the
transport layer connects applications on different hosts with a logical channel through the network with appropriate data exchange methods.
Underlying these layers are the networking technologies that
interconnect networks at their borders and exchange traffic across them.
The
Internet layer enables computers ("hosts") to identify each other via
Internet Protocol (IP) addresses, and route their traffic to each other via any intermediate (transit) networks. Last, at the bottom of the architecture is the
link layer, which provides logical connectivity between hosts on the same network link, such as a
local area network (LAN) or a
dial-up connection. The model, also known as
TCP/IP,
is designed to be independent of the underlying hardware used for the
physical connections, which the model does not concern itself with in
any detail. Other models have been developed, such as the
OSI model,
that attempt to be comprehensive in every aspect of communications.
While many similarities exist between the models, they are not
compatible in the details of description or implementation. Yet, TCP/IP
protocols are usually included in the discussion of OSI networking.
As
user data is processed through the protocol stack, each abstraction
layer adds encapsulation information at the sending host. Data is
transmitted over the wire at the link level between hosts and
routers. Encapsulation is removed by the receiving host. Intermediate
relays update link encapsulation at each hop, and inspect the IP layer
for routing purposes.
The most prominent component of the Internet model is the Internet Protocol (IP), which provides addressing systems, including
IP addresses, for computers on the network. IP enables internetworking and, in essence, establishes the Internet itself.
Internet Protocol Version 4
(IPv4) is the initial version used on the first generation of the
Internet and is still in dominant use. It was designed to address up to
~4.3 billion (10
9) hosts. However, the explosive growth of the Internet has led to
IPv4 address exhaustion, which entered its final stage in 2011,
when the global address allocation pool was exhausted. A new protocol
version, IPv6, was developed in the mid-1990s, which provides vastly
larger addressing capabilities and more efficient routing of Internet
traffic.
IPv6 is currently in growing
deployment around the world, since Internet address registries (
RIRs) began to urge all resource managers to plan rapid adoption and conversion.
IPv6 is not directly interoperable by design with IPv4. In
essence, it establishes a parallel version of the Internet not directly
accessible with IPv4 software. Thus, translation facilities must exist
for internet working or nodes must have duplicate networking software for
both networks. Essentially all modern computer operating systems
support both versions of the Internet Protocol. Network infrastructure,
however, has been lagging in this development. Aside from the complex
array of physical connections that make up its infrastructure, the
Internet is facilitated by bi- or multi-lateral commercial contracts,
e.g.,
peering agreements,
and by technical specifications or protocols that describe the exchange
of data over the network. Indeed, the Internet is defined by its
interconnections and routing policies.
Services
Many people use, erroneously, the terms
Internet and
World Wide Web, or just the
Web, interchangeably, but the two terms are not synonymous. The
World Wide Web is a primary application program that billions of people use on the Internet, and it has changed their lives immeasurably. However, the Internet provides many
network services, most prominently include
mobile apps such as
social media apps, the
World Wide Web,
electronic mail,
multiplayer online games,
Internet telephony, and
file sharing and
streaming media services.
World Wide Web
World Wide Web browser software, such as
Microsoft's
Internet Explorer/
Edge,
Mozilla Firefox,
Opera,
Apple's
Safari, and
Google Chrome,
lets users navigate from one web page to another via hyperlinks
embedded in the documents. These documents may also contain any
combination of
computer data, including graphics, sounds,
text,
video,
multimedia and interactive content that runs while the user is interacting with the page.
Client-side software can include animations,
games,
office applications and scientific demonstrations. Through
keyword-driven
Internet research using
search engines like
Yahoo!,
Bing and
Google,
users worldwide have easy, instant access to a vast and diverse amount
of online information. Compared to printed media, books, encyclopedias
and traditional libraries, the World Wide Web has enabled the
decentralization of information on a large scale.
The Web is therefore a global set of
documents,
images and other resources, logically interrelated by
hyperlinks and referenced with
Uniform Resource Identifiers (URIs). URIs symbolically identify services,
servers, and other databases, and the documents and resources that they can provide.
Hypertext Transfer Protocol (HTTP) is the main access protocol of the World Wide Web.
Web services also use HTTP to allow software systems to communicate in order to share and exchange business logic and data.
The Web has enabled individuals and organizations to
publish ideas and information to a potentially large
audience online at greatly reduced expense and time delay. Publishing a web page, a blog, or building a website involves little initial
cost
and many cost-free services are available. However, publishing and
maintaining large, professional web sites with attractive, diverse and
up-to-date information is still a difficult and expensive proposition.
Many individuals and some companies and groups use
web logs or blogs, which are largely used as easily updatable online diaries. Some commercial organizations encourage
staff
to communicate advice in their areas of specialization in the hope that
visitors will be impressed by the expert knowledge and free
information, and be attracted to the corporation as a result.
When the Web developed in the 1990s, a typical web page was stored in completed form on a web server, formatted in
HTML,
complete for transmission to a web browser in response to a request.
Over time, the process of creating and serving web pages has become
dynamic, creating a flexible design, layout, and content. Websites are
often created using
content management
software with, initially, very little content. Contributors to these
systems, who may be paid staff, members of an organization or the
public, fill underlying databases with content using editing pages
designed for that purpose while casual visitors view and read this
content in HTML form. There may or may not be editorial, approval and
security systems built into the process of taking newly entered content
and making it available to the target visitors.
Communication
Email
is an important communications service available on the Internet. The
concept of sending electronic text messages between parties in a way
analogous to mailing letters or memos predates the creation of the
Internet. Pictures, documents, and other files are sent as
email attachments. Emails can be
cc-ed to multiple
email addresses.
Internet telephony is another common communications service made possible by the creation of the Internet.
VoIP stands for Voice-over-
Internet Protocol, referring to the protocol that underlies all Internet communication. The idea began in the early 1990s with
walkie-talkie-like
voice applications for personal computers. In recent years many VoIP
systems have become as easy to use and as convenient as a normal
telephone. The benefit is that, as the Internet carries the voice
traffic, VoIP can be free or cost much less than a traditional telephone
call, especially over long distances and especially for those with
always-on Internet connections such as
cable or
ADSL and
mobile data. VoIP is maturing into a competitive alternative to traditional
telephone service. Interoperability between different providers has
improved and the ability to call or receive a call from a traditional
telephone is available. Simple, inexpensive VoIP network adapters are
available that eliminate the need for a personal computer.
Voice quality can still vary from call to call, but is often
equal to and can even exceed that of traditional calls. Remaining
problems for VoIP include
emergency telephone number
dialing and reliability. Currently, a few VoIP providers provide an
emergency service, but it is not universally available. Older
traditional phones with no "extra features" may be line-powered only and
operate during a power failure; VoIP can never do so without a
backup power source
for the phone equipment and the Internet access devices. VoIP has also
become increasingly popular for gaming applications, as a form of
communication between players. Popular VoIP clients for gaming include
Ventrilo and
Teamspeak. Modern video game consoles also offer VoIP chat features.
Data transfer
File sharing is an example of transferring large amounts of data across the Internet. A
computer file can be emailed to customers, colleagues and friends as an attachment. It can be uploaded to a website or
File Transfer Protocol (FTP) server for easy download by others. It can be put into a "shared location" or onto a
file server for instant use by colleagues. The load of bulk downloads to many users can be eased by the use of "
mirror" servers or
peer-to-peer networks. In any of these cases, access to the file may be controlled by user
authentication, the transit of the file over the Internet may be obscured by
encryption,
and money may change hands for access to the file. The price can be
paid by the remote charging of funds from, for example, a credit card
whose details are also passed – usually fully encrypted – across the
Internet. The origin and authenticity of the file received may be
checked by
digital signatures or by
MD5
or other message digests. These simple features of the Internet, over a
worldwide basis, are changing the production, sale, and distribution of
anything that can be reduced to a computer file for transmission. This
includes all manner of print publications, software products, news,
music, film, video, photography, graphics and the other arts. This in
turn has caused seismic shifts in each of the existing industries that
previously controlled the production and distribution of these products.
Streaming media
is the real-time delivery of digital media for the immediate
consumption or enjoyment by end users. Many radio and television
broadcasters provide Internet feeds of their live audio and video
productions. They may also allow time-shift viewing or listening such as
Preview, Classic Clips and Listen Again features. These providers have
been joined by a range of pure Internet "broadcasters" who never had
on-air licenses. This means that an Internet-connected device, such as a
computer or something more specific, can be used to access on-line
media in much the same way as was previously possible only with a
television or radio receiver. The range of available types of content is
much wider, from specialized technical
webcasts to on-demand popular multimedia services.
Podcasting is a variation on this theme, where – usually audio – material is downloaded and played back on a computer or shifted to a
portable media player
to be listened to on the move. These techniques using simple equipment
allow anybody, with little censorship or licensing control, to broadcast
audio-visual material worldwide.
Digital media streaming increases the demand for network
bandwidth. For example, standard image quality needs 1 Mbit/s link
speed for SD 480p, HD 720p quality requires 2.5 Mbit/s, and the
top-of-the-line HDX quality needs 4.5 Mbit/s for 1080p.
Webcams
are a low-cost extension of this phenomenon. While some webcams can
give full-frame-rate video, the picture either is usually small or
updates slowly. Internet users can watch animals around an African
waterhole, ships in the
Panama Canal, traffic at a local roundabout or monitor their own premises, live and in real time. Video
chat rooms and
video conferencing
are also popular with many uses being found for personal webcams, with
and without two-way sound. YouTube was founded on 15 February 2005 and
is now the leading website for free streaming video with a vast number
of users. It uses a HTML5 based web player by default to stream and show
video files. Registered users may upload an unlimited amount of video and build their own personal profile.
YouTube claims that its users watch hundreds of millions, and upload hundreds of thousands of videos daily.
Social impact
The Internet has enabled new forms of social interaction, activities,
and social associations. This phenomenon has given rise to the
scholarly study of the
sociology of the Internet.
Users
Internet users per 100 inhabitants
Internet usage has seen tremendous growth. From 2000 to 2009, the
number of Internet users globally rose from 394 million to 1.858
billion. By 2010, 22 percent of the world's population had access to computers with 1 billion
Google searches every day, 300 million Internet users reading blogs, and 2 billion videos viewed daily on
YouTube.
In 2014 the world's Internet users surpassed 3 billion or 43.6 percent
of world population, but two-thirds of the users came from richest
countries, with 78.0 percent of Europe countries population using the
Internet, followed by 57.4 percent of the Americas.
After English (27%), the most requested languages on the
World Wide Web
are Chinese (25%), Spanish (8%), Japanese (5%), Portuguese and German
(4% each), Arabic, French and Russian (3% each), and Korean (2%). By region, 42% of the world's
Internet users are based in Asia, 24% in Europe, 14% in North America, 10% in Latin America and the
Caribbean taken together, 6% in Africa, 3% in the Middle East and 1% in Australia/Oceania. The Internet's technologies have developed enough in recent years, especially in the use of
Unicode,
that good facilities are available for development and communication in
the world's widely used languages. However, some glitches such as
mojibake (incorrect display of some languages' characters) still remain.
In an American study in 2005, the percentage of men using the
Internet was very slightly ahead of the percentage of women, although
this difference reversed in those under 30. Men logged on more often,
spent more time online, and were more likely to be broadband users,
whereas women tended to make more use of opportunities to communicate
(such as email). Men were more likely to use the Internet to pay bills,
participate in auctions, and for recreation such as downloading music
and videos. Men and women were equally likely to use the Internet for
shopping and banking.
More recent studies indicate that in 2008, women significantly
outnumbered men on most social networking sites, such as Facebook and
Myspace, although the ratios varied with age. In addition, women watched more streaming content, whereas men downloaded more.
In terms of blogs, men were more likely to blog in the first place;
among those who blog, men were more likely to have a professional blog,
whereas women were more likely to have a personal blog.
Forecasts predict that 44% of the world's population will be users of the Internet by 2020. Splitting by country, in 2012 Iceland, Norway, Sweden, the Netherlands, and Denmark had the highest
Internet penetration by the number of users, with 93% or more of the population with access.
Several neologisms exist that refer to Internet users:
Netizen (as in "citizen of the net") refers to those
actively involved in improving
online communities, the Internet in general or surrounding political affairs and rights such as
free speech,
Internaut refers to operators or technically highly capable users of the Internet,
digital citizen refers to a person using the Internet in order to engage in society, politics, and government participation.
Usage
The Internet allows greater flexibility in working hours and
location, especially with the spread of unmetered high-speed
connections. The Internet can be accessed almost anywhere by numerous
means, including through
mobile Internet devices. Mobile phones,
datacards,
handheld game consoles and
cellular routers allow users to connect to the Internet
wirelessly.
Within the limitations imposed by small screens and other limited
facilities of such pocket-sized devices, the services of the Internet,
including email and the web, may be available. Service providers may
restrict the services offered and mobile data charges may be
significantly higher than other access methods.
Educational material at all levels from pre-school to post-doctoral is available from websites. Examples range from
CBeebies, through school and high-school revision guides and
virtual universities, to access to top-end scholarly literature through the likes of
Google Scholar. For
distance education, help with
homework
and other assignments, self-guided learning, whiling away spare time,
or just looking up more detail on an interesting fact, it has never been
easier for people to access educational information at any level from
anywhere. The Internet in general and the
World Wide Web in particular are important enablers of both
formal and
informal education.
Further, the Internet allows universities, in particular, researchers
from the social and behavioral sciences, to conduct research remotely
via virtual laboratories, with profound changes in reach and
generalizability of findings as well as in communication between
scientists and in the publication of results.
The low cost and nearly instantaneous sharing of ideas, knowledge, and skills have made
collaborative work dramatically easier, with the help of
collaborative software.
Not only can a group cheaply communicate and share ideas but the wide
reach of the Internet allows such groups more easily to form. An example
of this is the
free software movement, which has produced, among other things,
Linux,
Mozilla Firefox, and
OpenOffice.org (later forked into
LibreOffice). Internet chat, whether using an
IRC chat room, an
instant messaging system, or a
social networking
website, allows colleagues to stay in touch in a very convenient way
while working at their computers during the day. Messages can be
exchanged even more quickly and conveniently than via email. These
systems may allow files to be exchanged, drawings and images to be
shared, or voice and video contact between team members.
Content management
systems allow collaborating teams to work on shared sets of documents
simultaneously without accidentally destroying each other's work.
Business and project teams can share calendars as well as documents and
other information. Such collaboration occurs in a wide variety of areas
including scientific research, software development, conference
planning, political activism and creative writing. Social and political
collaboration is also becoming more widespread as both Internet access
and
computer literacy spread.
The Internet allows computer users to remotely access other
computers and information stores easily from any access point. Access
may be with
computer security,
i.e. authentication and encryption technologies, depending on the
requirements. This is encouraging new ways of working from home,
collaboration and information sharing in many industries. An accountant
sitting at home can
audit the books of a company based in another country, on a
server
situated in a third country that is remotely maintained by IT
specialists in a fourth. These accounts could have been created by
home-working bookkeepers, in other remote locations, based on
information emailed to them from offices all over the world. Some of
these things were possible before the widespread use of the Internet,
but the cost of private
leased lines
would have made many of them infeasible in practice. An office worker
away from their desk, perhaps on the other side of the world on a
business trip or a holiday, can access their emails, access their data
using
cloud computing, or open a
remote desktop session into their office PC using a secure
virtual private network
(VPN) connection on the Internet. This can give the worker complete
access to all of their normal files and data, including email and other
applications, while away from the office. It has been referred to among
system administrators as the Virtual Private Nightmare, because it extends the secure perimeter of a corporate network into remote locations and its employees' homes.
Social networking and entertainment
Many people use the World Wide Web to access news, weather and sports
reports, to plan and book vacations and to pursue their personal
interests. People use
chat, messaging and email to make and stay in touch with friends worldwide, sometimes in the same way as some previously had
pen pals.
Social networking websites such as
Facebook,
Twitter, and
Myspace
have created new ways to socialize and interact. Users of these sites
are able to add a wide variety of information to pages, to pursue common
interests, and to connect with others. It is also possible to find
existing acquaintances, to allow communication among existing groups of
people. Sites like
LinkedIn foster commercial and business connections. YouTube and
Flickr
specialize in users' videos and photographs. While social networking
sites were initially for individuals only, today they are widely used by
businesses and other organizations to promote their brands, to market
to their customers and to encourage posts to "
go viral". "Black hat" social media techniques are also employed by some organizations, such as
spam accounts and
astroturfing.
A risk for both individuals and organizations writing posts
(especially public posts) on social networking websites, is that
especially foolish or controversial posts occasionally lead to an
unexpected and possibly large-scale backlash on social media from other
Internet users. This is also a risk in relation to controversial
offline
behavior, if it is widely made known. The nature of this backlash can
range widely from counter-arguments and public mockery, through insults
and
hate speech, to, in extreme cases, rape and death
threats. The
online disinhibition effect
describes the tendency of many individuals to behave more stridently or
offensively online than they would in person. A significant number of
feminist women have been the target of various forms of
harassment
in response to posts they have made on social media, and Twitter in
particular has been criticised in the past for not doing enough to aid
victims of online abuse.
For organizations, such a backlash can cause overall
brand damage,
especially if reported by the media. However, this is not always the
case, as any brand damage in the eyes of people with an opposing opinion
to that presented by the organization could sometimes be outweighed by
strengthening the brand in the eyes of others. Furthermore, if an
organization or individual gives in to demands that others perceive as
wrong-headed, that can then provoke a counter-backlash.
Some websites, such as
Reddit, have rules forbidding the posting of
personal information of individuals (also known as
doxxing),
due to concerns about such postings leading to mobs of large numbers of
Internet users directing harassment at the specific individuals thereby
identified. In particular, the Reddit rule forbidding the posting of
personal information is widely understood to imply that all identifying
photos and names must be
censored in Facebook
screenshots
posted to Reddit. However, the interpretation of this rule in relation
to public Twitter posts is less clear, and in any case, like-minded
people online have many other ways they can use to direct each other's
attention to public social media posts they disagree with.
Children also face dangers online such as
cyberbullying and
approaches by sexual predators,
who sometimes pose as children themselves. Children may also encounter
material which they may find upsetting, or material which their parents
consider to be not age-appropriate. Due to naivety, they may also post
personal information about themselves online, which could put them or
their families at risk unless warned not to do so. Many parents choose
to enable
Internet filtering,
and/or supervise their children's online activities, in an attempt to
protect their children from inappropriate material on the Internet. The
most popular social networking websites, such as Facebook and Twitter,
commonly forbid users under the age of 13. However, these policies are
typically trivial to circumvent by registering an account with a false
birth date, and a significant number of children aged under 13 join such
sites anyway. Social networking sites for younger children, which claim
to provide better levels of protection for children, also exist.
The Internet has been a major outlet for leisure activity since its inception, with entertaining
social experiments such as
MUDs and
MOOs being conducted on university servers, and humor-related
Usenet groups receiving much traffic. Many
Internet forums have sections devoted to games and funny videos. The
Internet pornography and
online gambling
industries have taken advantage of the World Wide Web, and often
provide a significant source of advertising revenue for other websites.
Although many governments have attempted to restrict both industries'
use of the Internet, in general, this has failed to stop their
widespread popularity.
Another area of leisure activity on the Internet is
multiplayer gaming.
This form of recreation creates communities, where people of all ages
and origins enjoy the fast-paced world of multiplayer games. These range
from
MMORPG to
first-person shooters, from
role-playing video games to
online gambling. While online gaming has been around since the 1970s, modern modes of online gaming began with subscription services such as
GameSpy and
MPlayer.
Non-subscribers were limited to certain types of game play or certain
games. Many people use the Internet to access and download music, movies
and other works for their enjoyment and relaxation. Free and fee-based
services exist for all of these activities, using centralized servers
and distributed peer-to-peer technologies. Some of these sources
exercise more care with respect to the original artists' copyrights than
others.
Internet usage has been correlated to users' loneliness.
Lonely people tend to use the Internet as an outlet for their feelings
and to share their stories with others, such as in the "
I am lonely will anyone speak to me" thread.
Cybersectarianism
is a new organizational form which involves: "highly dispersed small
groups of practitioners that may remain largely anonymous within the
larger social context and operate in relative secrecy, while still
linked remotely to a larger network of believers who share a set of
practices and texts, and often a common devotion to a particular leader.
Overseas supporters provide funding and support; domestic
practitioners distribute tracts, participate in acts of resistance, and
share information on the internal situation with outsiders.
Collectively, members and practitioners of such sects construct viable
virtual communities of faith, exchanging personal testimonies and
engaging in the collective study via email, on-line chat rooms, and
web-based message boards."
In particular, the British government has raised concerns about the
prospect of young British Muslims being indoctrinated into Islamic
extremism by material on the Internet, being persuaded to join
terrorist groups such as the so-called "
Islamic State", and then potentially committing acts of terrorism on returning to Britain after fighting in Syria or Iraq.
Cyberslacking
can become a drain on corporate resources; the average UK employee
spent 57 minutes a day surfing the Web while at work, according to a
2003 study by Peninsula Business Services.
Internet addiction disorder is excessive computer use that interferes with daily life.
Nicholas G. Carr believes that Internet use has other
effects on individuals, for instance improving skills of scan-reading and
interfering with the deep thinking that leads to true creativity.
Electronic business
Electronic business (
e-business) encompasses business processes spanning the entire
value chain: purchasing,
supply chain management,
marketing,
sales,
customer service, and business relationship.
E-commerce seeks to add revenue streams using the Internet to build and enhance relationships with clients and partners. According to
International Data Corporation,
the size of worldwide e-commerce, when global business-to-business and
-consumer transactions are combined, equate to $16 trillion for 2013. A
report by Oxford Economics adds those two together to estimate the total
size of the
digital economy at $20.4 trillion, equivalent to roughly 13.8% of global sales.
Author
Andrew Keen,
a long-time critic of the social transformations caused by the
Internet, has recently focused on the economic effects of consolidation
from Internet businesses. Keen cites a 2013
Institute for Local Self-Reliance
report saying brick-and-mortar retailers employ 47 people for every $10
million in sales while Amazon employs only 14. Similarly, the
700-employee room rental start-up
Airbnb was valued at $10 billion in 2014, about half as much as
Hilton Hotels, which employs 152,000 people. And car-sharing Internet startup
Uber employs 1,000 full-time employees and is valued at $18.2 billion, about the same valuation as
Avis and
Hertz combined, which together employ almost 60,000 people.
Telecommuting
Telecommuting is the performance within a traditional worker and employer relationship when it is facilitated by tools such as
groupware,
virtual private networks,
conference calling,
videoconferencing, and
voice over IP
(VOIP) so that work may be performed from any location, most
conveniently the worker's home. It can be efficient and useful for
companies as it allows workers to communicate over long distances,
saving significant amounts of travel time and cost. As
broadband
Internet connections become commonplace, more workers have adequate
bandwidth at home to use these tools to link their home to their
corporate
intranet and internal communication networks.
Collaborative publishing
Wikis
have also been used in the academic community for sharing and
dissemination of information across institutional and international
boundaries. In those settings, they have been found useful for collaboration on
grant writing,
strategic planning, departmental documentation, and committee work. The
United States Patent and Trademark Office uses a wiki to allow the public to collaborate on finding
prior art relevant to examination of pending patent applications.
Queens, New York has used a wiki to allow citizens to collaborate on the design and planning of a local park. The
English Wikipedia has the largest user base among wikis on the World Wide Web and ranks in the top 10 among all Web sites in terms of traffic.
Politics and political revolutions
Banner in Bangkok during the 2014 Thai coup d'état, informing the Thai public that 'like' or 'share' activities on social media could result in imprisonment (observed June 30, 2014).
The Internet has achieved new relevance as a political tool. The presidential campaign of
Howard Dean
in 2004 in the United States was notable for its success in soliciting
donation via the Internet. Many political groups use the Internet to
achieve a new method of organizing for carrying out their mission,
having given rise to
Internet activism, most notably practiced by rebels in the
Arab Spring.
The New York Times suggested that
social media
websites, such as Facebook and Twitter, helped people organize the
political revolutions in Egypt, by helping activists organize protests,
communicate grievances, and disseminate information.
Many have understood the Internet as an extension of the
Habermasian notion of the
public sphere,
observing how network communication technologies provide something like
a global civic forum. However, incidents of politically motivated
Internet censorship have now been recorded in many countries, including western democracies.
Philanthropy
The spread of low-cost Internet access in developing countries has opened up new possibilities for
peer-to-peer
charities, which allow individuals to contribute small amounts to
charitable projects for other individuals. Websites, such as
DonorsChoose and
GlobalGiving,
allow small-scale donors to direct funds to individual projects of
their choice. A popular twist on Internet-based philanthropy is the use
of
peer-to-peer lending for charitable purposes.
Kiva
pioneered this concept in 2005, offering the first web-based service to
publish individual loan profiles for funding. Kiva raises funds for
local intermediary
microfinance
organizations which post stories and updates on behalf of the
borrowers. Lenders can contribute as little as $25 to loans of their
choice, and receive their money back as borrowers repay. Kiva falls
short of being a pure peer-to-peer charity, in that loans are disbursed
before being funded by lenders and borrowers do not communicate with
lenders themselves.
However, the recent spread of low-cost Internet access in
developing countries has made genuine international person-to-person philanthropy increasingly feasible. In 2009, the US-based nonprofit
Zidisha
tapped into this trend to offer the first person-to-person microfinance
platform to link lenders and borrowers across international borders
without intermediaries. Members can fund loans for as little as a
dollar, which the borrowers then use to develop business activities that
improve their families' incomes while repaying loans to the members
with interest. Borrowers access the Internet via public cybercafes,
donated laptops in village schools, and even smart phones, then create
their own profile pages through which they share photos and information
about themselves and their businesses. As they repay their loans,
borrowers continue to share updates and dialogue with lenders via their
profile pages. This direct web-based connection allows members
themselves to take on many of the communication and recording tasks
traditionally performed by local organizations, bypassing geographic
barriers and dramatically reducing the cost of microfinance services to
the entrepreneurs.
Security
Internet resources, hardware, and software components are the target
of criminal or malicious attempts to gain unauthorized control to cause
interruptions, commit fraud, engage in blackmail or access private
information.
Malware
Surveillance
The vast majority of computer surveillance involves the monitoring of
data and
traffic on the Internet. In the United States for example, under the
Communications Assistance For Law Enforcement Act,
all phone calls and broadband Internet traffic (emails, web traffic,
instant messaging, etc.) are required to be available for unimpeded
real-time monitoring by Federal law enforcement agencies.
Packet capture is the monitoring of data traffic on a
computer network.
Computers communicate over the Internet by breaking up messages
(emails, images, videos, web pages, files, etc.) into small chunks
called "packets", which are routed through a network of computers, until
they reach their destination, where they are assembled back into a
complete "message" again.
Packet Capture Appliance
intercepts these packets as they are traveling through the network, in
order to examine their contents using other programs. A packet capture
is an information
gathering tool, but not an
analysis
tool. That is it gathers "messages" but it does not analyze them and
figure out what they mean. Other programs are needed to perform
traffic analysis and sift through intercepted data looking for important/useful information. Under the
Communications Assistance For Law Enforcement Act
all U.S. telecommunications providers are required to install packet
sniffing technology to allow Federal law enforcement and intelligence
agencies to intercept all of their customers'
broadband Internet and
voice over Internet protocol (VoIP) traffic.
The large amount of data gathered from packet capturing requires
surveillance software that filters and reports relevant information,
such as the use of certain words or phrases, the access of certain types
of web sites, or communicating via email or chat with certain parties. Agencies, such as the
Information Awareness Office,
NSA,
GCHQ and the
FBI, spend billions of dollars per year to develop, purchase, implement, and operate systems for interception and analysis of data. Similar systems are operated by
Iranian secret police to identify and suppress dissidents. The required hardware and software was allegedly installed by German
Siemens AG and Finnish
Nokia.
Censorship
In Norway, Denmark, Finland, and Sweden, major Internet service
providers have voluntarily agreed to restrict access to sites listed by
authorities. While this list of forbidden resources is supposed to
contain only known child pornography sites, the content of the list is
secret.
Many countries, including the United States, have enacted laws against
the possession or distribution of certain material, such as
child pornography, via the Internet, but do not mandate filter software. Many free or commercially available software programs, called
content-control software
are available to users to block offensive websites on individual
computers or networks, in order to limit access by children to
pornographic material or depiction of violence.
Performance
As the Internet is a heterogeneous network, the physical characteristics, including for example the
data transfer rates of connections, vary widely. It exhibits
emergent phenomena that depend on its large-scale organization.
Outages
An Internet blackout or outage can be caused by local signalling interruptions. Disruptions of
submarine communications cables may cause blackouts or slowdowns to large areas, such as in the
2008 submarine cable disruption.
Less-developed countries are more vulnerable due to a small number of
high-capacity links. Land cables are also vulnerable, as in 2011 when a
woman digging for scrap metal severed most connectivity for the nation
of Armenia. Internet blackouts affecting almost entire countries can be achieved by governments as a form of
Internet censorship, as in the blockage of the
Internet in Egypt, whereby approximately 93% of networks were without access in 2011 in an attempt to stop mobilization for
anti-government protests.
Energy use
In 2011, researchers estimated the energy used by the Internet to be
between 170 and 307 GW, less than two percent of the energy used by
humanity. This estimate included the energy needed to build, operate,
and periodically replace the estimated 750 million laptops, a billion
smart phones and 100 million servers worldwide as well as the energy
that routers, cell towers, optical switches, Wi-Fi transmitters and
cloud storage devices use when transmitting Internet traffic.
