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An internet compute
الأربعاء 6 يناير - 8:30
An internet is a more general term
informally used to describe any set of interconnected computer networks that are connected by internetworking.
The Internet, or simply the Net, is the
publicly accessible worldwide system of interconnected computer networks that transmit data by packet switching using a standardized Internet Protocol (IP) and many other protocols.
It is made up of thousands of smaller commercial, academic, domestic and
government networks. It carries various information and services, such as electronic mail, online chat, and the interlinked web pages and other documents of the World Wide Web.
Creation of the Internet
During the 1950s, several communications
researchers realized that there was a need to allow general communication
between users of various computers and communications networks. This led to
research into decentralized networks,
queuing theory, and packet switching. The subsequent creation of ARPANET in the United States in turn catalyzed a wave of
technical developments that made it the basis for the development of the
Internet.
The first TCP/IP wide area network was operational in 1984
when the United States'
National Science
Foundation (NSF) constructed a university network backbone that
would later become the NSFNet. It was then followed
by the opening of the network to commercial interests in 1995.
Important seperate networks that have successfully entered the Internet include
Usenet, Bitnet and the various commercial and educational X.25
networks such as Compuserve and JANET.
The collective network gained a public face in the 1990s.
In August 1991
Tim Berners-Lee publicized his new World Wide
Web project, two years after he had begun creating HTML,
HTTP
and the first few web pages at CERN in Switzerland. In 1993
the Mosaic web browser
version 1.0 was released, and by late 1994
there was growing public interest in the previously academic/technical
Internet. By 1996 the word "Internet" was common
public currency, but it referred almost entirely to the World Wide Web.
Meanwhile, over the course of the decade, the Internet
successfully accommodated the majority of previously existing public computer
networks (although some networks such as FidoNet have remained separate). 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.
Today's Internet
Apart from the incredibly complex physical connections
that make up its infrastructure, the Internet is held together by bi- or
multi-lateral commercial contracts (for example peering agreements) and by technical
specifications or protocols
that describe how to exchange data over the network.
Unlike older communications systems, the Internet protocol
suite was deliberately designed to be independent of the underlying
physical medium. Any communications network, wired or wireless, that can carry
two-way digital data can carry Internet traffic. Thus, Internet packets flow
through wired networks like copper wire, coaxial cable, and fiber optic; and
through wireless networks like Wi-Fi. Together, all these
networks, sharing the same high-level protocols, form the Internet.
The Internet protocols originate from discussions within
the Internet Engineering Task Force (IETF) and its working groups,
which are open to public participation and review. These committees produce
documents that are known as Request for Comments
documents (RFCs). Some RFCs are raised to the status of Internet Standard by the Internet Architecture
Board (IAB).
Some of the most used protocols in the Internet protocol
suite are IP, TCP,
UDP, DNS, PPP, SLIP, ICMP, POP3, IMAP,
SMTP,
HTTP,
HTTPS, SSH, Telnet, FTP, LDAP,
SSL, and TLS.
Some of the popular services on the Internet that make
use of these protocols are e-mail, Usenet newsgroups, file sharing, Instant Messenger, the World Wide Web, Gopher, session access,
WAIS,
finger, IRC, MUDs,
and MUSHs. Of these, e-mail and the World Wide Web
are clearly the most used, and many other services are built upon them, such as
mailing lists and web logs. The Internet makes it possible to
provide real-time services such as Internet radio and webcasts that can be accessed from anywhere in
the world.
Some other popular services of the Internet were not
created this way, but were originally based on proprietary systems. These
include IRC, ICQ,
AIM, and Gnutella.
There have been many analyses of the Internet and its
structure. For example, it has been determined that the Internet IP routing
structure and hypertext links of the World Wide Web are examples of scale-free networks.
Similar to how the commercial Internet providers connect
via Internet exchange
points, research networks tend to interconnect into large
subnetworks such as:
These in turn are built around relatively smaller
networks. See also the list of academic computer network organizations
In network schematic diagrams, the Internet is often
represented by a cloud symbol, into and out of which network
communications can pass.
Internet culture
The World Wide Web
Through keyword-driven Internet research using search engines like Google,
millions worldwide have easy, instant access to a vast and diverse amount of
online information. Compared to encyclopedias and traditional libraries, the World Wide Web has enabled a
sudden and extreme decentralization of information and data.
Some companies and individuals have adopted the use of
'web-logs' or blogs, which are largely used as
easily-updatable online diaries. Some commercial organizations encourage staff
to fill them with advice on 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. One example of this practice is Microsoft, via whose product developers publish their personal blogs in order
to pique the public's interest in their work.
For more information on the distinction between the World
Wide Web and the Internet itself — as in everyday use the two are sometimes
confused — see Dark internet where
this is discussed in more detail.
Remote access
The Internet allows computer users to connect to other
computers and information stores easily, wherever they may be across the world.
They may do this with or without the use of security, authentication and
encryption technologies, depending on the requirements.
This is encouraging new ways of home-working,
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 book-keepers, in other remote locations, based on
information e-mailed 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 his or her desk, perhaps the
other side of the world on a business trip or a holiday, can open a remote desktop
session into his or her normal office PC using a secure Virtual Private
Network (VPN) connection via the Internet. This gives him or her complete
access to all their normal files and data, including e-mail and other
applications, while they are away.
Collaboration
This low-cost and nearly instantaneous sharing of ideas,
knowledge and skills has revolutionized some, and given rise to whole new,
areas of human activity. One example of this is the collaborative development and distribution of Free/Libre/Open-Source
Software (FLOSS) such as Linux, Mozilla and OpenOffice.org. See Collaborative software.
File-sharing
A computer file can be
e-mailed to customers, colleagues and friends as
an attachment. It
can be uploaded to a website or 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
networking.
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 before or
after access to the file is given. The price can be paid by the remote charging
of funds from, for example a credit card whose
details are also passed - hopefully fully encrypted - across the Internet. The
origin and authenticity of the file received may be checked by digital signatures or by MD5
message digests.
These simple features of the Internet, over a world-wide
basis, are changing the basis for the production, sale and distribution of many
types of product, wherever they can be reduced to a computer file for
transmission. This includes all manner of office documents, publications,
software products, music, photography, video, animations, graphics
and the other arts. This in turn is causing seismic shifts in each of the
existing industry associations, such as the RIAA
and MPAA, that previously controlled the production
and distribution of these products.
Streaming
media and VoIP
Many existing radio and television broadcasters have
provided Internet 'feeds' of their live audio and video streams (for example,
the BBC). They have been joined by a range of pure
Internet 'broadcasters' who never had on-air licences. 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 TV or radio receiver. The range of material is much wider, from
pornography to highly specialised technical web-casts. The simplest equipment
can allow anybody, with little censorship or licencing control, to broadcast on
a worldwide basis. Time-shift viewing or listening is not a problem as the BBC
have shown with their Preview, Classic Clips and Listen Again features.
Web-cams can be seen as an even lower-budget extension of
this phenomenon. In this case the picture may update only slowly - perhaps once
every few seconds or slower, but Internet users can watch animals around an
African waterhole, ships in the Panama Canal or the traffic at a local
roundabout live and in real time. Video chat rooms, video conferencing,
and remote controllable webcams have become popular. Some people install
webcams in their bedrooms that can be accessed by other voyeurs, often with
two-way sound. There are even sex-workers who operate commercial
bedrooms-cum-studios.
VoIP stands for
Voice over IP, where IP refers to the
Internet Protocol that underlies all Internet communication. This phenomenon began
as an optional two-way voice extension to some of the Instant Messaging systems that took off around
the turn of the millennium. In recent years many people and organisations have
made VoIP systems as easy to use and as convenient as a normal telephone. The
benefit is that, as the actual voice traffic is carried by the Internet, VoIP
is free or costs much less than an actual telephone call, especially over long
distances and especially for those with always-on ADSL
or DSL
Internet connections anyway. The disadvantages are that it is still difficult
to initiate a call with someone, unless they also have a VoIP phone or are at
their computer and that there are still several competing standards that are
mitigating against universal acceptance.
In all of these cases, existing large organisations, that
have grown accustomed to regular incomes for their services, are finding
increased competition in their service areas, coming directly from the
Internet. While newcomers strive to make these inroads, the traditional industries
are having to adapt, adopt, complain or suffer. Meanwhile the consumer in each
case most probably benefits from the increased range of services and possible
price reductions. Some worry about censorship and control while others see a
continuing globalisation of culture and norms.
Language
The most prevalent language for communication on the
Internet is English. This may
be due to the Internet's origins or to the growing role of English as an
international language. It may also be due to the poor capability of early
computers to handle characters other than those in the basic western alphabet (see Unicode).
After English (56 % of websites) the most-used
languages on the world wide web are German 8 %, French 6 %, Japanese 5 % and Spanish 3 %. These statistics are probably
already out of date.
The Internet's technologies have developed enough in
recent years that good facilities are available for development and
communication in most widely used languages. However, some glitches such as mojibake still remain.
Cultural awareness
From a cultural awareness perspective, the Internet has
been both an advantage and a liability. For people who are interested in other
cultures it provides a significant amount of information and an interactivity
that would be unavailable otherwise. However, for people who are not interested
in other cultures there is some evidence indicating that the Internet enables
them to avoid contact to a greater degree than ever before.
Censorship
Some countries such as Iran
and the People's Republic
of China, restrict what people in their countries can see on the
internet. Some through government sponsored censoring filters, others by means
of law or culture, making the propagation of targeted materials extremely hard.
At the moment most Internet content is available regardless of where one is in
the world, so long as one has the means of connecting to it.
Internet access
Common methods of home access include dial-up, landline broadband
(over coaxial cable, fiber optic or copper wires), Wi-Fi,
satellite and cell phones.
Public places to use
the Internet include libraries and Internet cafes, where computers with Internet
connections are available. There are also Internet access points in many public
places like airport halls, in some cases just for brief use while standing.
Various terms are used, such as "public Internet kiosk", "public
access terminal", and "Web payphone". Many hotels now also have public
terminals, though these are usually fee based.
Wi-Fi provides wireless access to computer
networks, and therefore can do so to the Internet itself. Hotspots providing such access include Wifi-cafes, where a would-be user needs to bring
their own wireless-enabled devices such as a laptop or PDA.
These services may be free to all, free to customers only, or fee-based. A
hotspot need not be limited to a confined location. Whole campuses and parks
have been enabled, even entire cities. Grassroots efforts have led to wireless community
networks.
Apart from Wi-Fi, there have been experiments with
proprietary mobile wireless networks like Ricochet, various high-speed data services over
cellular or mobile phone networks, and fixed wireless services. These services
have not enjoyed widespread success due to their high cost of deployment, which
is passed on to users in high usage fees. New wireless technologies such as WiMAX
have the potential to alleviate these concerns and enable simple and cost
effective deployment of metropolitan area
networks covering large, urban areas. There is a growing trend
towards wireless mesh networks which
offer a decentralised and redundant infrastructure and are often considered the
future of the Internet.
Broadband access
over power lines was approved in 2004 in the United States
in the face of stiff resistance from the amateur radio community. The problem with
modulating a carrier signal onto power lines is that an above-ground power line
can act as a giant antenna and jam long-distance radio frequencies used by
amateurs, seafarers and others.
Countries where Internet access is available to a
majority of the population include Germany, India,
China, Chile,
Iceland, Finland, Sweden, Australia, Denmark, the United States, Canada, Britain, The Netherlands, Japan,
Singapore, Taiwan, South Korea and Norway. The use of the Internet around the world has been
growing rapidly over the last decade, although the growth rate seems to have
slowed somewhat after 2000. The phase of rapid growth is ending in
industrialized countries, as usage becomes ubiquitous there, but the spread
continues in Africa, Latin America, the Caribbean and the Middle East.
However, there are still problems for many. ADSL
and other broadband
access is rare or nonexistent in most developing countries.
Even in developed countries, high prices, mediocre performance and access
restrictions often limit its uptake. Within individual countries, wide
differences may exist between larger cities (often having multiple providers of
broadband access) and some rural areas, where no broadband access may be
available at all.
The expansion of the availability of Internet access is a
way to bridge the so-called digital divide.
Naming conventions
In formal usage, Internet is traditionally written
with a capital first letter. The Internet Society, the Internet Engineering
Task Force, the Internet Corporation for Assigned Names and Numbers,
the World Wide Web
Consortium, and several other Internet-related organizations all use
this convention in their publications. In English grammar, proper nouns are
capitalized.
The majority of newspapers, newswires, periodicals, and
technical journals also capitalize the term. Examples include the New York Times, the Associated Press, Time, The Times of India,
Hindustan Times
and Communications of
the ACM.
In less formal usage, the capital letter is often dropped
(internet), and many people are not aware that there is a convention of
using a capital letter. There are also some people who argue that internet
is the correct formal term.
Since 2000, a significant number of
publications have switched to using internet. Among them are the Economist, the Financial Times, the London Times, and the Sydney Morning Herald.
As of 2005, most publications using internet
appear to be located outside of North America. One American news source, Wired News, is well-known for its use of the
lowercase spelling.
Leisure
The Internet has been a major source of leisure since
before the World Wide Web, with entertaining social experiments such as MOOs
being conducted on university servers, and humor-related USENET groups receiving much of the main traffic. Today, many
Internet forums have sections devoted to neta;
short cartoons in the form of Flash movies are also
popular.
The pornography and gambling industries have both taken full
advantage of the World Wide Web, and often provide a significant source of
advertising revenue for other Web sites. Although many governments have
attempted to put restrictions on both industries' use of the Internet, this has
generally failed to stop their widespread popularity.
One main area of leisure on the Internet is multiplayer gaming.
This form of leisure creates communities, bringing people of all ages and
origins to enjoy the fast-paced world of multiplayer games. These range from MMORPG to first-person shooters,
from role-playing games
to online gambling.
This has revolutionized the way many people interact and spend their free time
on the Internet.
Online gaming began with services such as GameSpy and
MPlayer, which players of games would typically subscribe to. Non-subscribers
were limited to certain types of gameplay or certain games. With the release of
Diablo by Blizzard Entertainment, gamers were treated to a built in online game
service that was free of charge. With Blizzard's next game, StarCraft, the
gaming world saw an explosion in the numbers of players using the Internet to
play multi-player games. StarCraft may have been the first non-MMO game in
which most players utilized the online gameplay as opposed to the single-player
gameplay.
Online gaming has progressed so much in the last
10 years that gamers earn a living from being a professional at the subject by
winning tournaments and prizes as well as signing sponsor deals. Because there is a large support
for certain online games, a new community has been born for people modding games, where users edit games to add a whole
new element to it. This is how games such as Counter-Strike
were born from the Half-Life Gaming Engine.
A complex system
Many computer
scientists see the Internet as a "prime example of a large-scale, highly
engineered, yet highly complex system" (Willinger, et al). The Internet is
extremely heterogeneous. (For instance, data transfer rates and physical
characteristics of connections vary widely.) The Internet exhibits "emergent phenomena" that depend on
its large-scale organization. For example, data transfer rates exhibit temporal
self-similarity.
Marketing
The Internet has also
become a big market, and the biggest companies today have grown by taking
advantage of the efficient low-cost advertising and commerce through the Internet. It is the fastest
way to spread information to a vast community of people all at once. The
Internet has revolutionized shopping –– a person can
order a CD online and receive it in the mail
within a couple of days, or download it directly in
some cases.
informally used to describe any set of interconnected computer networks that are connected by internetworking.
The Internet, or simply the Net, is the
publicly accessible worldwide system of interconnected computer networks that transmit data by packet switching using a standardized Internet Protocol (IP) and many other protocols.
It is made up of thousands of smaller commercial, academic, domestic and
government networks. It carries various information and services, such as electronic mail, online chat, and the interlinked web pages and other documents of the World Wide Web.
Creation of the Internet
During the 1950s, several communications
researchers realized that there was a need to allow general communication
between users of various computers and communications networks. This led to
research into decentralized networks,
queuing theory, and packet switching. The subsequent creation of ARPANET in the United States in turn catalyzed a wave of
technical developments that made it the basis for the development of the
Internet.
The first TCP/IP wide area network was operational in 1984
when the United States'
National Science
Foundation (NSF) constructed a university network backbone that
would later become the NSFNet. It was then followed
by the opening of the network to commercial interests in 1995.
Important seperate networks that have successfully entered the Internet include
Usenet, Bitnet and the various commercial and educational X.25
networks such as Compuserve and JANET.
The collective network gained a public face in the 1990s.
In August 1991
Tim Berners-Lee publicized his new World Wide
Web project, two years after he had begun creating HTML,
HTTP
and the first few web pages at CERN in Switzerland. In 1993
the Mosaic web browser
version 1.0 was released, and by late 1994
there was growing public interest in the previously academic/technical
Internet. By 1996 the word "Internet" was common
public currency, but it referred almost entirely to the World Wide Web.
Meanwhile, over the course of the decade, the Internet
successfully accommodated the majority of previously existing public computer
networks (although some networks such as FidoNet have remained separate). 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.
Today's Internet
Apart from the incredibly complex physical connections
that make up its infrastructure, the Internet is held together by bi- or
multi-lateral commercial contracts (for example peering agreements) and by technical
specifications or protocols
that describe how to exchange data over the network.
Unlike older communications systems, the Internet protocol
suite was deliberately designed to be independent of the underlying
physical medium. Any communications network, wired or wireless, that can carry
two-way digital data can carry Internet traffic. Thus, Internet packets flow
through wired networks like copper wire, coaxial cable, and fiber optic; and
through wireless networks like Wi-Fi. Together, all these
networks, sharing the same high-level protocols, form the Internet.
The Internet protocols originate from discussions within
the Internet Engineering Task Force (IETF) and its working groups,
which are open to public participation and review. These committees produce
documents that are known as Request for Comments
documents (RFCs). Some RFCs are raised to the status of Internet Standard by the Internet Architecture
Board (IAB).
Some of the most used protocols in the Internet protocol
suite are IP, TCP,
UDP, DNS, PPP, SLIP, ICMP, POP3, IMAP,
SMTP,
HTTP,
HTTPS, SSH, Telnet, FTP, LDAP,
SSL, and TLS.
Some of the popular services on the Internet that make
use of these protocols are e-mail, Usenet newsgroups, file sharing, Instant Messenger, the World Wide Web, Gopher, session access,
WAIS,
finger, IRC, MUDs,
and MUSHs. Of these, e-mail and the World Wide Web
are clearly the most used, and many other services are built upon them, such as
mailing lists and web logs. The Internet makes it possible to
provide real-time services such as Internet radio and webcasts that can be accessed from anywhere in
the world.
Some other popular services of the Internet were not
created this way, but were originally based on proprietary systems. These
include IRC, ICQ,
AIM, and Gnutella.
There have been many analyses of the Internet and its
structure. For example, it has been determined that the Internet IP routing
structure and hypertext links of the World Wide Web are examples of scale-free networks.
Similar to how the commercial Internet providers connect
via Internet exchange
points, research networks tend to interconnect into large
subnetworks such as:
- GEANT
- Internet2
- GLORIAD
These in turn are built around relatively smaller
networks. See also the list of academic computer network organizations
In network schematic diagrams, the Internet is often
represented by a cloud symbol, into and out of which network
communications can pass.
Internet culture
The World Wide Web
Through keyword-driven Internet research using search engines like Google,
millions worldwide have easy, instant access to a vast and diverse amount of
online information. Compared to encyclopedias and traditional libraries, the World Wide Web has enabled a
sudden and extreme decentralization of information and data.
Some companies and individuals have adopted the use of
'web-logs' or blogs, which are largely used as
easily-updatable online diaries. Some commercial organizations encourage staff
to fill them with advice on 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. One example of this practice is Microsoft, via whose product developers publish their personal blogs in order
to pique the public's interest in their work.
For more information on the distinction between the World
Wide Web and the Internet itself — as in everyday use the two are sometimes
confused — see Dark internet where
this is discussed in more detail.
Remote access
The Internet allows computer users to connect to other
computers and information stores easily, wherever they may be across the world.
They may do this with or without the use of security, authentication and
encryption technologies, depending on the requirements.
This is encouraging new ways of home-working,
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 book-keepers, in other remote locations, based on
information e-mailed 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 his or her desk, perhaps the
other side of the world on a business trip or a holiday, can open a remote desktop
session into his or her normal office PC using a secure Virtual Private
Network (VPN) connection via the Internet. This gives him or her complete
access to all their normal files and data, including e-mail and other
applications, while they are away.
Collaboration
This low-cost and nearly instantaneous sharing of ideas,
knowledge and skills has revolutionized some, and given rise to whole new,
areas of human activity. One example of this is the collaborative development and distribution of Free/Libre/Open-Source
Software (FLOSS) such as Linux, Mozilla and OpenOffice.org. See Collaborative software.
File-sharing
A computer file can be
e-mailed to customers, colleagues and friends as
an attachment. It
can be uploaded to a website or 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
networking.
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 before or
after access to the file is given. The price can be paid by the remote charging
of funds from, for example a credit card whose
details are also passed - hopefully fully encrypted - across the Internet. The
origin and authenticity of the file received may be checked by digital signatures or by MD5
message digests.
These simple features of the Internet, over a world-wide
basis, are changing the basis for the production, sale and distribution of many
types of product, wherever they can be reduced to a computer file for
transmission. This includes all manner of office documents, publications,
software products, music, photography, video, animations, graphics
and the other arts. This in turn is causing seismic shifts in each of the
existing industry associations, such as the RIAA
and MPAA, that previously controlled the production
and distribution of these products.
Streaming
media and VoIP
Many existing radio and television broadcasters have
provided Internet 'feeds' of their live audio and video streams (for example,
the BBC). They have been joined by a range of pure
Internet 'broadcasters' who never had on-air licences. 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 TV or radio receiver. The range of material is much wider, from
pornography to highly specialised technical web-casts. The simplest equipment
can allow anybody, with little censorship or licencing control, to broadcast on
a worldwide basis. Time-shift viewing or listening is not a problem as the BBC
have shown with their Preview, Classic Clips and Listen Again features.
Web-cams can be seen as an even lower-budget extension of
this phenomenon. In this case the picture may update only slowly - perhaps once
every few seconds or slower, but Internet users can watch animals around an
African waterhole, ships in the Panama Canal or the traffic at a local
roundabout live and in real time. Video chat rooms, video conferencing,
and remote controllable webcams have become popular. Some people install
webcams in their bedrooms that can be accessed by other voyeurs, often with
two-way sound. There are even sex-workers who operate commercial
bedrooms-cum-studios.
VoIP stands for
Voice over IP, where IP refers to the
Internet Protocol that underlies all Internet communication. This phenomenon began
as an optional two-way voice extension to some of the Instant Messaging systems that took off around
the turn of the millennium. In recent years many people and organisations have
made VoIP systems as easy to use and as convenient as a normal telephone. The
benefit is that, as the actual voice traffic is carried by the Internet, VoIP
is free or costs much less than an actual telephone call, especially over long
distances and especially for those with always-on ADSL
or DSL
Internet connections anyway. The disadvantages are that it is still difficult
to initiate a call with someone, unless they also have a VoIP phone or are at
their computer and that there are still several competing standards that are
mitigating against universal acceptance.
In all of these cases, existing large organisations, that
have grown accustomed to regular incomes for their services, are finding
increased competition in their service areas, coming directly from the
Internet. While newcomers strive to make these inroads, the traditional industries
are having to adapt, adopt, complain or suffer. Meanwhile the consumer in each
case most probably benefits from the increased range of services and possible
price reductions. Some worry about censorship and control while others see a
continuing globalisation of culture and norms.
Language
The most prevalent language for communication on the
Internet is English. This may
be due to the Internet's origins or to the growing role of English as an
international language. It may also be due to the poor capability of early
computers to handle characters other than those in the basic western alphabet (see Unicode).
After English (56 % of websites) the most-used
languages on the world wide web are German 8 %, French 6 %, Japanese 5 % and Spanish 3 %. These statistics are probably
already out of date.
The Internet's technologies have developed enough in
recent years that good facilities are available for development and
communication in most widely used languages. However, some glitches such as mojibake still remain.
Cultural awareness
From a cultural awareness perspective, the Internet has
been both an advantage and a liability. For people who are interested in other
cultures it provides a significant amount of information and an interactivity
that would be unavailable otherwise. However, for people who are not interested
in other cultures there is some evidence indicating that the Internet enables
them to avoid contact to a greater degree than ever before.
Censorship
Some countries such as Iran
and the People's Republic
of China, restrict what people in their countries can see on the
internet. Some through government sponsored censoring filters, others by means
of law or culture, making the propagation of targeted materials extremely hard.
At the moment most Internet content is available regardless of where one is in
the world, so long as one has the means of connecting to it.
Internet access
Common methods of home access include dial-up, landline broadband
(over coaxial cable, fiber optic or copper wires), Wi-Fi,
satellite and cell phones.
Public places to use
the Internet include libraries and Internet cafes, where computers with Internet
connections are available. There are also Internet access points in many public
places like airport halls, in some cases just for brief use while standing.
Various terms are used, such as "public Internet kiosk", "public
access terminal", and "Web payphone". Many hotels now also have public
terminals, though these are usually fee based.
Wi-Fi provides wireless access to computer
networks, and therefore can do so to the Internet itself. Hotspots providing such access include Wifi-cafes, where a would-be user needs to bring
their own wireless-enabled devices such as a laptop or PDA.
These services may be free to all, free to customers only, or fee-based. A
hotspot need not be limited to a confined location. Whole campuses and parks
have been enabled, even entire cities. Grassroots efforts have led to wireless community
networks.
Apart from Wi-Fi, there have been experiments with
proprietary mobile wireless networks like Ricochet, various high-speed data services over
cellular or mobile phone networks, and fixed wireless services. These services
have not enjoyed widespread success due to their high cost of deployment, which
is passed on to users in high usage fees. New wireless technologies such as WiMAX
have the potential to alleviate these concerns and enable simple and cost
effective deployment of metropolitan area
networks covering large, urban areas. There is a growing trend
towards wireless mesh networks which
offer a decentralised and redundant infrastructure and are often considered the
future of the Internet.
Broadband access
over power lines was approved in 2004 in the United States
in the face of stiff resistance from the amateur radio community. The problem with
modulating a carrier signal onto power lines is that an above-ground power line
can act as a giant antenna and jam long-distance radio frequencies used by
amateurs, seafarers and others.
Countries where Internet access is available to a
majority of the population include Germany, India,
China, Chile,
Iceland, Finland, Sweden, Australia, Denmark, the United States, Canada, Britain, The Netherlands, Japan,
Singapore, Taiwan, South Korea and Norway. The use of the Internet around the world has been
growing rapidly over the last decade, although the growth rate seems to have
slowed somewhat after 2000. The phase of rapid growth is ending in
industrialized countries, as usage becomes ubiquitous there, but the spread
continues in Africa, Latin America, the Caribbean and the Middle East.
However, there are still problems for many. ADSL
and other broadband
access is rare or nonexistent in most developing countries.
Even in developed countries, high prices, mediocre performance and access
restrictions often limit its uptake. Within individual countries, wide
differences may exist between larger cities (often having multiple providers of
broadband access) and some rural areas, where no broadband access may be
available at all.
The expansion of the availability of Internet access is a
way to bridge the so-called digital divide.
Naming conventions
In formal usage, Internet is traditionally written
with a capital first letter. The Internet Society, the Internet Engineering
Task Force, the Internet Corporation for Assigned Names and Numbers,
the World Wide Web
Consortium, and several other Internet-related organizations all use
this convention in their publications. In English grammar, proper nouns are
capitalized.
The majority of newspapers, newswires, periodicals, and
technical journals also capitalize the term. Examples include the New York Times, the Associated Press, Time, The Times of India,
Hindustan Times
and Communications of
the ACM.
In less formal usage, the capital letter is often dropped
(internet), and many people are not aware that there is a convention of
using a capital letter. There are also some people who argue that internet
is the correct formal term.
Since 2000, a significant number of
publications have switched to using internet. Among them are the Economist, the Financial Times, the London Times, and the Sydney Morning Herald.
As of 2005, most publications using internet
appear to be located outside of North America. One American news source, Wired News, is well-known for its use of the
lowercase spelling.
Leisure
The Internet has been a major source of leisure since
before the World Wide Web, with entertaining social experiments such as MOOs
being conducted on university servers, and humor-related USENET groups receiving much of the main traffic. Today, many
Internet forums have sections devoted to neta;
short cartoons in the form of Flash movies are also
popular.
The pornography and gambling industries have both taken full
advantage of the World Wide Web, and often provide a significant source of
advertising revenue for other Web sites. Although many governments have
attempted to put restrictions on both industries' use of the Internet, this has
generally failed to stop their widespread popularity.
One main area of leisure on the Internet is multiplayer gaming.
This form of leisure creates communities, bringing people of all ages and
origins to enjoy the fast-paced world of multiplayer games. These range from MMORPG to first-person shooters,
from role-playing games
to online gambling.
This has revolutionized the way many people interact and spend their free time
on the Internet.
Online gaming began with services such as GameSpy and
MPlayer, which players of games would typically subscribe to. Non-subscribers
were limited to certain types of gameplay or certain games. With the release of
Diablo by Blizzard Entertainment, gamers were treated to a built in online game
service that was free of charge. With Blizzard's next game, StarCraft, the
gaming world saw an explosion in the numbers of players using the Internet to
play multi-player games. StarCraft may have been the first non-MMO game in
which most players utilized the online gameplay as opposed to the single-player
gameplay.
Online gaming has progressed so much in the last
10 years that gamers earn a living from being a professional at the subject by
winning tournaments and prizes as well as signing sponsor deals. Because there is a large support
for certain online games, a new community has been born for people modding games, where users edit games to add a whole
new element to it. This is how games such as Counter-Strike
were born from the Half-Life Gaming Engine.
A complex system
Many computer
scientists see the Internet as a "prime example of a large-scale, highly
engineered, yet highly complex system" (Willinger, et al). The Internet is
extremely heterogeneous. (For instance, data transfer rates and physical
characteristics of connections vary widely.) The Internet exhibits "emergent phenomena" that depend on
its large-scale organization. For example, data transfer rates exhibit temporal
self-similarity.
Marketing
The Internet has also
become a big market, and the biggest companies today have grown by taking
advantage of the efficient low-cost advertising and commerce through the Internet. It is the fastest
way to spread information to a vast community of people all at once. The
Internet has revolutionized shopping –– a person can
order a CD online and receive it in the mail
within a couple of days, or download it directly in
some cases.
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