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Internet terms you should know

Internet
Extranet
Intranet
ARPANET
World Wide Web

Internet
The Internet is an international network. It is a global network that connects millions of networks together using a suite of protocols called the TCP/IP. These networks belong to different categories of organizations, such as educational institutions, government, military and commercial services. The Internet evolved from a small network of four computers called the ARPANET (Advance Research Projects Agency Network). The word Internet is a combination of two words; ‘International and network’. ‘Inter’ stands for International, while ‘net’ stands for network.

Extranet
The extranet is a network of computers that belongs to a private organization, but allows some external bodies or organizations to access the network for communal or business purposes. The extranet is based on the Internet technology.

Intranet
The intranet is a network of computers that belongs to a private organization and can only be accessed by members of that organization. The intranet is used for e-mails, information sharing and other forms of communication within the organization. The intranet is also based on the Internet technology, which includes the use of the TCP/IP protocols.

ARPANET
ARPANET means Advance Research Projects Agency Network. The Internet originated from ARPNET in 1969.

World Wide Web
The World Wide Web is a technology built on top on the Internet to allow access and sharing of information over the Internet. It uses the HTTP (Hypertext Transfer Protocol) as a set of rules that defines how information is accessed.
The World Wide Web allow information on the Internet to be displayed as web documents or Web Pages from different servers, which are linked together by hyperlinks.
These Web Pages are written in HTML (Hypertext Mark-Up Language). Web pages can be viewed using a software called the web browser; example of which are Microsoft Window Explorer or Netscape. Text on Web Pages may contain video, sound, text, graphics or images.

It is important to note that the WWW is just a technology built over the Internet. It is part of the Internet and just one of the ways in which information is shared over the Internet.