These days everybody is on the internet. If you are reading this article then you are most probably on the internet. But what is the internet. Who owns or controls it. How it works. I am writing this article in an effort to explore there questions. I have found the following facts by searching on what else the Internet!
Wikipedia describes internet as 'The Internet is a global system of interconnected computer networks that use the standard Internet Protocol Suite (TCP/IP) to serve billions of users worldwide.'
Wikipedia also tells that the Internet has no centralized governance in either technological implementation or policies for access and usage; each constituent network sets its own standards.
It is a "network of networks" that consists of millions of private and public, academic, business, and government networks of local to global scope that are linked by copper wires, fiber-optic cables, wireless connections, and other technologies.
Only the overreaching definitions of the two principal name spaces in the Internet, the Internet Protocol address space and the Domain Name System, are directed by a maintainer organization, the Internet Corporation for Assigned Names and Numbers (ICANN).
The estimated population of Internet users is 1.67 billion as of June 30, 2009.
The complex communications infrastructure of the Internet consists of its hardware components and a system of software layers that control various aspects of the architecture.
The responsibility for the architectural design of the Internet software systems has been delegated to 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 discussions and final standards are published in a series of publications, each called a Request for Comments (RFC), freely available 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.
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 (RFC 1122, RFC 1123).
Information is moved around the Internet by packet switching using the standardized Internet Protocol Suite (TCP/IP).
The Internet Protocol Suite (commonly known as TCP/IP) is the set of communications protocols used for the Internet and other similar networks.
It is named from two of the most important protocols in it: the Transmission Control Protocol (TCP) and the Internet Protocol (IP), which were the first two networking protocols defined in this standard.
Layers of Internet
Good link for finding more on Internet Protocol Suite : http://en.wikipedia.org/wiki/Internet_Protocol_Suite
The most prominent component of the Internet model is the Internet Protocol (IP) which provides addressing systems (IP addresses) for computers on the Internet. IP enables internetworking and essentially establishes the Internet itself.
Internet is an example of internetworking. Internetworking is the practice of connecting a computer network with other networks through the use of gateways that provide a common method of routing information packets between the networks. The resulting system of interconnected networks is called an internetwork, or simply an internet.
IP Version 4 (IPv4) is the initial version used on the first generation of the today's Internet and is still in dominant use. It was designed to address up to ~4.3 billion (109) Internet hosts.
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 commercial deployment phase around the world and Internet address registries (RIRs) have begun to urge all resource managers to plan rapid adoption and conversion.
IPv6 is not interoperable with IPv4.
Practically the Internet is defined by its interconnections and routing policies.
Peering is a voluntary interconnection of administratively separate Internet networks for the purpose of exchanging traffic between the customers of each network.
The pure definition of peering is settlement-free or "sender keeps all," meaning that neither party pays the other for the exchanged traffic, instead, each derives revenue from its own customers.
The Internet is a collection of separate and distinct networks, each one operating under a common framework of globally unique IP addressing and global BGP routing.
Peering requires physical interconnection of the networks, an exchange of routing information through the Border Gateway Protocol (BGP) routing protocol and is often accompanied by peering agreements of varying formality, from "handshake" to thick contracts.
The Internet is based on the principle of global reachability (sometimes called end-to-end reachability), which means that any Internet user can reach any other Internet user as though they were on the same network.
The Internet is a globally distributed network comprising many voluntarily interconnected autonomous networks.
To maintain interoperability, all technical and policy aspects of the underlying core infrastructure and the principal name spaces are administered by the Internet Corporation for Assigned Names and Numbers (ICANN), headquartered in Marina del Rey, California.
ICANN is the authority that 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, in which names and numbers are uniquely assigned, are essential for the global reach of the Internet.
The US government continues to have the primary role in approving changes to the DNS root zone that lies at the heart of the domain name system.
ICANN's role in coordinating the assignment of unique identifiers distinguishes it as perhaps the only central coordinating body on the global Internet.
Internet and World Wide Web (www) are different.
The World Wide Web is a global set of documents, images and other resources, logically interrelated by hyperlinks and referenced with Uniform Resource Identifiers (URIs).
URIs allow providers to symbolically identify services and clients to locate and address web servers, file servers, and other databases that store documents and provide resources and access them using the Hypertext Transfer Protocol (HTTP), the primary carrier protocol of the Web.
HTTP is only one of the hundreds of communication protocols used on the Internet.
World Wide Web browser software lets users navigate from one web page to another via hyperlinks embedded in the documents.
What does WWW(W3) define?
the idea of a boundless world of information interconnected by hypertext links for easy point-and-click access
the Uniform Resource Identifier (URI) concept, an addressing system that the project implemented to make this world possible, despite many different protocols
the Hypertext Transfer Protocol (HTTP), a network protocol used to transfer web pages
the Hypertext Markup Language (HTML) a content formatting framework that every WWW client can understand, and is used for the formatting of text, menus and simple on-line help information across the net
Many web addresses begin with www, because of the long-standing practice of naming Internet hosts (servers) according to the services they provide.
The hostname for a web server is often www, as it is ftp for an FTP server, and news or nntp for a USENET news server.
These host names appear as Domain Name System (DNS) subdomain names, as in www.example.com.
The use of such subdomain names is not required by any technical or policy standard
These subdomain prefixes have no consequence; they are simply chosen names.
Many web servers are set up such that both the domain by itself (e.g., example.com) and the www subdomain (e.g., www.example.com) refer to the same site, others require one form or the other, or they may map to different web sites.
Many formal standards and other technical specifications define the operation of different aspects of the World Wide Web
Many of the documents are the work of the World Wide Web Consortium (W3C), headed by Berners-Lee but some are produced by the Internet Engineering Task Force (IETF) and other organizations
Fundamental Web Standards
HTML (Defined by W3C)
XHTML (Defined by W3C)
CSS (Defined by W3C)
DOM (Recommendations by W3C)
Uniform Resource Identifier (URI) (Defined by RFC 3986 of IETF)
HyperText Transfer Protocol (HTTP) (Defined by RFC 2616 of IETF)
XML (Defined by W3C)
The 'http://' or 'https://' part of web addresses does have meaning: These refer to Hypertext Transfer Protocol and to HTTP Secure and so define the communication protocol that will be used to request and receive the page and all its images and other resource
The following are famous World Wide Web browsers:
These documents may also contain any combination of computer data, including graphics, sounds, text, video, multimedia and interactive content including games, office applications and scientific demonstrations.
E-mail 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.
Internet telephony is another common communications service made possible by the creation of the Internet.
E-mail systems are based on a store-and-forward model in which e-mail computer server systems accept, forward, deliver and store messages on behalf of users, who only need to connect to the e-mail infrastructure, typically an e-mail server, with a network-enabled device for the duration of message submission or retrieval.
Originally, e-mail was always transmitted directly from one user's device to another's; nowadays this is rarely the case.
An electronic mail message consists of two components
It contains control information, including, minimally, an originator's email address and one or more recipient addresses
It contains e-mails content.
Originally a text-only communications medium, email was extended to carry multi-media content attachments, which were standardized in with RFC 2045 through RFC 2049, collectively called, Multipurpose Internet Mail Extensions (MIME).
The foundation for today's global Internet e-mail service was created in the early ARPANET and standards for encoding of messages were proposed as early as 1973 (RFC 561). An e-mail sent in the early 1970s looked very similar to one sent on the Internet today.
The Internet e-mail message format is defined in RFC 5322.
Data transfer application over internet may use authentication, encryption and digital signatures.
Internet also allows streaming of audio and video media.
The prevalent language for communication on the Internet is English although other languages are catching up.
UNICODE is the standard which helps to encode text in nearly all major world languages.