Overview of the Internet and the World Wide Web
CIW Website Design Manager Course Section 1, Part A, Chapter 1
History of the Internet and World Wide Web
The Internet was formed in 1968, when the US Department of Defense created the Advanced Research Project Agency (ARPA), also called the Defense Advanced Research Projects Agency (DARPA). It's first global computer network, Advanced Research Projects Agency Network (ARPANET), allowed government and researchers to interact, and to work from any location on the network.
The World Wide Web was created in 1989 by Tim Berners-Lee when he proposed a hypertext system that would enable scientists studying high-energy physics to share information more efficiently. The proposal was important because it involved an interface that would be consistent across all platforms. The World Wide Web interface was completed in March 1991 and the files became available in the Usenet newsgroup, alt.hypertext, in August 1991.
Timeline
The following timeline chronicles the development of the Internet from it's earliest days:
| 1957 | The US government creates the Advanced Research Projects Agency (ARPA) to research emerging technologies deemed to risky for civilian development. |
| 1969 | DOD commissions the creation of ARPAnet to study networking protocols. |
| 1973 | TCP/IP protocol invented. |
| 1983 | University of California releases a variant of a Unix operating system, which popularises the use of TCP/IP. |
| 1986 | The National Science Foundation created NSFnet. This connects five supercomputing centres in the country. It runs at speeds of 56Kbps. |
| 1989 | NSFnet upgrades due to 100,000 hosts on the Internet. It now uses a 1.5Mbps T1. |
| 1990 | ARPAnet no longer exists, leaving in it's wake the NSFnet and the Internet. |
| 1992 | Hosting on the Internet reaches the 1 million mark. |
| 1995 | With over 4 million hosts on the Internet, the NSF decommissions NSFnet. The government role is over in creating the Internet. |
How the Internet Works
An important characteristic of computer networks is scalability. A small network may consist of no more than two interconnected computers. A large network may contain thousands of computers of different types located all over the world. A very large network is made by connecting smaller networks together and would be called an internetwork.
The Internet is a global internetwork. It is a vast collection of computers and networks, connected so that they may exchange information.
TCP/IP
Transmission Control Protocol / Internet Protocol (TCP/IP) is the communication method of the Internet. TCP/IP provides a fast and reliable method for transferring data around the Internet. There may be many possible routes from the source host to the destination host, TCP/IP and the network routers will find the best route at all times, even when there is a failure somewhere on the network. A failure does not require the re-transmission of the entire message, as TCP/IP breaks the message into "packets", only the failed packet needs to be resent.
IP Addresses
Every host on the Internet must have a unique IP Address to identify it. Most of us are used to using domain names when looking for a web site or an FTP server, but this is just a friendly/human interface for the IP Address.