Web Browsers
Browsers are the pieces of software that we use for looking at web pages. (Point of order here: Web Pages, or the World Wide Web (www), represent only a part of what is know as the internet, which also covers email, usenet etc).
The first real browser was called Mozaic - this dates back to the stone age of Computing, as was a very basic, text based browser, suitable for viewing text based documents (The WWW was initially envisiaged as a way to let academics share papers, reports and other resources).
Mozaic morphed into Netscape, who produced a browser called Navigator, whilst Microsoft came from behind to produce Internet Explorer (IE) (A version of which we use at school). This triggered what became known as the Browser Wars - Netscape had the better product, but Microsoft had a dominant position in the market, and started giving away a copy of Internet Explorer free with every copy of Windows. This eventually went to court (but far too late for Netscape, who's product, despite being superior, became a minority browser).
Fast forward a few years: Internet Explorer is generally the default web browser, but some people aren't too happy. Microsoft has a habit of implementing open standards differently from everyone else - the upshot of this is that a page written for IE might not display properly in another browser.
Netscape decided to take a revolutionary step. They released the source code (i.e. the programming code that makes a programme) to the Open Source Community. (Open Source is a term given to software that is developed in a more open, non secretive enviroment, leading to faster development times, as anyone at all can join in, if they are good enough!)
A Community project called Mozilla was set up on the internet to manage the development of a new rendering engine code named Gecko (The bit of the browser that decides how a page is going ot be displayed).
After a year or so, Gecko was up and running: Because it was an open source project, Netwcape decided that they would use the Gecko engine in their newest version of Navigator (a significant improvement). Mozilla the web broswer was released into the wild, and feedback started to flow in.
Mozilla has now gone through a series of evolutions, and is now a fully featured, extendible and easy to use browser, ready to compete (mostly) with IE. Netscape has now been taken over by AOL Time Warner (There are even rumours that they will replace AOL's rendering engine (currently based on IE) with a Gecko variant). Safari, the Apple browser uses the Gecko engine.
The other main competitor to IE at the moment is called Opera. This is a versatile, feature rich browser, that is available in 2 forms - a free, ad-sponsored download, and a paid for, ad-free version.