This article is about the Internet, the extensive, worldwide computer network available to the public. An internet is a more general term for any set of interconnected computer networks that are connected by internetworking.
The Internet is the publicly available worldwide system of interconnected computer networks that transmit data by packet switching using a standardised Internet Protocol (IP). It is made up of thousands of other, smaller commercial, academic, 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. Because this is by far the largest, most extensive internet (with a small i) in the world, it is simply called the Internet (with a capital I).
Creation of the Internet
Main article: History of the Internet
The core networks forming the Internet started out in 1969 as the ARPANET, created by the United States Department of Defense Advanced Research Projects Agency (ARPA). Some early research which contributed to the ARPANET included work on decentralised networks, queueing theory, and packet switching. On January 1, 1983, the ARPANET changed its core networking protocols from NCP to TCP/IP, marking the start of the Internet as we know it today.
Another important step in the development was the National Science Foundation's (NSF) building of a university backbone, the NSFNet, in 1986. Important disparate networks that have successfully been accommodated within the Internet include Usenet and Bitnet.
During the 1990s, the Internet successfully accommodated the majority of previously existing computer networks (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 one company from exerting control over the network.
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 agnostic with regard to 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 popular services on the Internet that make use of these protocols are e-mail, Usenet newsgroups, file sharing, 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 web radio and webcasts that can be accessed from anywhere in the world.
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.
The World Wide Web
Through keyword-driven Internet research, using search engines, like Google, millions worldwide have easy, instant access to a vast amount and diversity of online information. Compared to encyclopedias and traditional libraries, the Internet has enabled a sudden and extreme decentralization of information and data.
See World Wide Web.
The Internet allows computer users easily to connect to other computers and information stores 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 their desk, perhaps the other side of the world on a business trip or a holiday, can open a remote desktop session into their normal office PC using a secure Virtual Private Network (VPN) connection via the Internet. This gives him or her completely normally access to all their normal files and data, including e-mail and other applications, while they are away.
This low-cost and nearly instantaneous sharing of ideas, knowledge and skills has revolutionised some, and given rise to whole new, areas of human activity. One example of this is the collaborative development and distribution of FLOSS (Free, Libre and Open-Source Software) such as Linux, Mozilla and OpenOffice.org.
A few other exmples include Wikipedia, a collaboratively edited and maintained free encyclopedia, the Urban Dictionary project and TEIS - the UK Telemedicine and E-health Information Service for those working in the field of telemedicine, telecare and ehealth.
A computer file can be e-mailed to customers, colleagues and friends as an attachment. It can be uploaded to a web site or FTP server for easy download by others. It can be put into a 'shared location'File_server" title ="File server">file server for instant use by colleagues. The load of bulk downloads to many users can be eased by the use of 'Mirror_%28computing%29" title ="Mirror (computing)">mirror'Peer-to-peer" title ="Peer-to-peer">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 industries that previously controlled the production and distribution of these products.
The most used language for communications on the Internet is English, due to the Internet'Alphabet" title ="Alphabet">alphabet.
The 'Mojibake" title ="Mojibake">mojibake still remain.
Using the Internet, people with the rarest of interests or conditions may communicate and collaborate through myriad methods, without the impediments of distance.
Current and potential problems
The Internet, along with its benefits, has a lot of negative publicity associated with it ranging from genuine concerns to tabloid scaremongering.
According to children'Child_pornography" title ="Child pornography">child pornography offences have increased by over 1000% since the Internet was first available to the public in the late 1980s. With the recent growth in Chat rooms and instant messaging services in the late 1990s, the potential for a new form of child abuse has emerged: so-called grooming. This involves a paedophile pretending to be a child in a chat room/instant message conversation, to gain the trust of a child before arranging to meet up.
Copyright infringement has also been the focus of much media attention, mainly through peer-to-peer filesharing software, but also through private members-only chatrooms, so-called warez sites (which openly offer illegal copies of software or the means to crack copy protection), or even the sale of counterfeit CDs, DVDs and software masquerading as legitimate product. Many ordinary Internet users are less concerned about the actual infringement itself but more about the effect on the Internet as a whole if tighter controls result from the infringement.
In the 1980s and early 1990s, when very few people had access to the Internet, viruses were not a huge problem. They did exist and did cause just as much damage to computers as modern viruses can today, but there was no fast-moving epidemic because there was no means for a virus to directly infect other computers. Before the Internet, the only way for a computer to be infected was through use of a removable disc that was itself infected. As a result, virus infections were mercifully rare.
All that changed with the widespread growth of the Internet. With near-universal Internet access among computer users in developed countries, and the proliferation of high-speed broadband Internet connections, a virus on one person's computer can infect thousands of other computers. In fact, much of the disruption from virus outbreaks is caused not by the payload of the virus (e.g. deleting hard drive, shutting down computer every five minutes), but by the Internet congestion caused by the virus spreading itself.
Main article: Security cracking
When computers were stand alone machines (or at most connected to a company's internal network), to steal data from a system an intruder had to physically steal it. The Internet means that data from an insecure site could be stolen by someone working two blocks from the site, or just as easily from another country.
A recent high-profile, high-cost example of this was when the entire source code for Half Life 2 was copied from the developer'September_2003" title ="September 2003">September 2003 before the attack, and was eventually released on November 16 2004.
Very few people outside the technical community are aware of the future problems posed by the Internet's archaic technology. It was originally designed for a small number of research institutions to share research data, and was never intended for the multi-billion user behemoth the modern Internet has become.
One serious problem is that the IP address (a unique number assigned to each Internet user that functions much like a street address in the real world) will run out eventually. Despite an estimated world population of over six billion, there are only a little over four billion different IP address combinations possible under the current system — see IPv4 address exhaustion for more information. This also doesn't take into account the fact that there is not a 1:1 person to computer ratio in current computerised countries, where many people will have a desktop machine at home, a laptop machine for on the go, another desktop machine at work, and an e-mail mobile phone, all requiring their own IP address.
This could pose serious problems in the future as more and more nations expand their computer infrastructure (the vast majority of the world's population does not currently use the Internet, the so-called digital divide) and even now efforts are proceeding to find new ways of running the Internet. The new version of the Internet Protocol, IPv6, which expands the address space of the Internet, is one proposal for how to deal with some of the technical problems caused by the growth of the Internet.
A recently recognized problem with the Internet arises from the fact that by promoting free speech and communications between geographically dispersed members of subcultures, the Internet enables such people to encourage each other in holding on to beliefs which may be considered deviant by society as a whole. With most subcultures, this is not a problem; indeed, the whole point of free speech is to encourage a diversity of ideas, many of which will seem strange. But as long as those ideas do not involve violence against other persons or the government, they are tolerated as harmless.
The problem is when the subculture at issue contains beliefs which promote highly self-destructive behaviors that are consistent with mental illness. There are Web sites that explicitly promote anorexia, apotemnophilia, necrophilia, and suicide as valuable and desirable.
Relatives of people who use such Web sites have lobbied Internet service providers to shut them down, but have encountered widespread indifference that is a direct consequence of the libertarian attitudes common in the computer industry.
This unique and troubling aspect of network-facilitated communications was not foreseen. Scientists, philosophers and journalists are still feeling their way around the edges of this problem; it raises difficult issues involving individual autonomy, health care policy, and the boundaries of free speech. The fundamental question comes down to: Should people be allowed to encourage each other to kill or maim themselves?
There will probably be more controversy in the future, as yet more self-destructive subcultures go online and are discovered by the general public.
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 public places like airport halls, sometimes just for brief use while standing. Various terms are used, such as "public Internet kiosk", "public access terminal", "Web payphone".
Wi-Fi provides wireless access to the Internet. Hotspots providing such access include Wifi-cafes, where a would-be user needs to bring their own wireless-enabled devices such as a notebook 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 an entire downtown area. 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.
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 over power lines is that a poorly insulated power line can act as a giant antenna and completely jam radio frequencies used by amateurs.
Countries where Internet access is a commodity used by a majority of the population include Iceland, Sweden, Denmark, The Netherlands 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.
The expansion of the availability of Internet access is a way to bridge the so-called digital divide.
- List of Internet topics
- Art on the Internet
- Bogon filtering
- Dark web
- Democracy on the Internet
- Dynamics of the Internet
- File Sharing
- Friendship on the Internet
- Hacktivism or Hacker culture
- International Freedom of Expression eXchange - monitors Internet censorship around the world
- Humor on the Internet
- Minitel, a French predecessor to the Internet
- Network Mapping
- Open Directory Project
- Slang on the Internet
- Trolls and trolling
- Web browser
- Web hosting
External links - General
- The Internet Society (ISOC)
- Internet Mapping Project
- Web content by language (old)
- Access and usage statistics: , , ,  (pdf)
- Access at home, by native language
- Internet World Usage Statistics
- Internet Directory @ dmoz
External links - Articles
- World of Ends, What the Internet Is and How to Stop Mistaking It for Something Else by Doc Searls and David Weinberger
- John Walker: The Digital Imprimatur
- addressingtheworld.info - website accompanying a book (ISBN 0742528103) on the history of DNS
- How Stuff Works explanation of the Infrastructure of the Internet
- "It's Just the 'internet' Now" - Wired.com article by Tony Long
- The Internet as a new mass medium
External links - History
- The Internet Society History Page
- How the Internet Came to Be
- Hobbes' Internet Timeline v7.0
- History of the Internet links
- RFC 801, planning the TCP/IP switchover
- - A searchable database of old cached versions of websites dating back to 1996
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