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Introduction
What is the Internet?
The internet is made up of millions of computers linked together around the world in such a way that information can be sent from any computer to any other 24 hours a day. These computers can be in homes, schools, universities, government departments, or businesses small and large. They can be any type of computer and be single personal computers or workstations on a school or a company network. The internet is often described as 'a network of networks' because all the smaller networks of
organizations are linked together into the one giant network called the internet. All computers are pretty much equal once connected to the internet, the only difference will be the speed of the connection which is dependent on your Internet Service Provider and your own modem.
Click ME to see an animation of how this works.
The internet has developed a very strong community base where information, software and expert advice are freely shared and for this reason users have developed a very strong protective stance on freedom of speech, freedom from commercial interests, netiquette and unsuitable material on the web.
Why would you want to use it?
There are so many things you can do and participate in once connected to the internet. They include using a range of services to communicate and share information and things quickly and inexpensively with tens of millions of people, both young and old and from diverse cultures around the world. For example:And as well as using the Internet for receiving things you will be able to
publish information about your school, hobbies or interests.
A Brief History of Cyberspace
Although it may seem like a new idea, the net has actually been around for over 40 years. It all began in the US during the Cold War, as a university experiment in military communications. By linking lots of computers together in a network, rather than serially (in a straight line), the Pentagon thought that in the event of a nuclear attack on the US it was unlikely that the entire network would be damaged, and therefore they would still be able to send and receive
intelligence.
At first each computer was physically linked by cable to the next computer, but this approach has obvious limitations, which led to the development of networks utilizing the telephone system. Predictably, people found that nuclear strike or not, they could talk to each other using this computer network, and some university students started using this network to do their homework together.
It seems a natural human characteristic to want to communicate, and once people realized that they could talk to other people via this computer network they began to demand access, although initially the users were only from the university and government sectors. But more and more people could see the potential of computer networks, and various community groups developed networks separate from the official networks for the use of their local communities.
The sum of all these various local, regional and national networks is the Internet as we experience it today, an ever expanding network of people, computers and information coming together in ways the Pentagon never dreamed of 40 years ago. So what began as an exercise in military paranoia has become a method of global communication.
"Cyberspace" is a term coined by William Gibson in his fantasy novel Neuromancer to describe the "world" of computers, and the society that gathers around them. Gibson's fantasy of a world of connected computers has moved into a present reality in the form of the Internet. In cyberspace people "exist" in the ether--you meet them electronically, in a disembodied, faceless form.
The Internet & the World Wide Web
Sometimes people use the words Internet and World Wide Web (WWW) synonymously but they are different. The WWW is a component of the Internet that presents information in a graphical interface. You can think of the WWW as the illustrated version of the Internet. It began in the late 1980's when physicist Dr.
Berners-Lee wrote a small computer program for his own personal use. This program allowed pages, within his computer, to be linked together using keywords. It soon became possible to link documents in different computers, as long as they were connected to the Internet. The document formatting language used to link documents is called HTML (Hypertext Markup Language.)
The Web remained primarily text based until 1992. Two events occurred that year that forever changed the way the Web looked. Marc Andreesen developed a new computer program called the NCSA Mosaic and gave it away! The NCSA Mosaic was the first Web browser.
The browser made it easier to access the different Web sites that had started to appear. Soon Web sites contained more than just text, they also had sound and video files. The development of the WWW has been the catalyst for the popularity of the internet and is also the easiest part of the internet to use. We now have Internet Chat, Discussion Groups, Internet Phone capabilities, Video conferencing, News Groups, Interactive Multimedia, Games and so much more.
TCP/IP
TCP/IP is a communications protocol used to transfer digital data around the internet. TCP and IP were developed by a Department of Defense (DOD) research project to connect different networks designed by different vendors into a network of networks (the "Internet"). TCP/IP is often referred to as the 'internet protocol'.
As with all communications protocols, TCP/IP is composed of layers:
IP - is responsible for moving packet of data from node to node. IP forwards each packet based on a four byte
destination address (the IP number). The Internet authorities assign ranges of numbers to different organizations.
The organizations assign groups of their numbers to departments. IP operates on gateway machines that move
data from department to organization to region and then around the world.
TCP - is responsible for verifying the correct delivery of data from client to server. Data can be lost in the
intermediate network. TCP adds support to detect errors or lost data and to trigger retransmission until the data is
correctly and completely received.
Sockets - is a name given to the package of subroutines that provide access to TCP/IP on most systems.
©
State of Victoria (Department of Education, Employment & Training)
Initiative of the SOFWeb Project Contact:
SOFWeb
Last Updated: August 11, 2000
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