GIS stands for Geographical Information Systems. Most people are happy using Google Earth for looking around their local area, looking at their houses, and having a go on the flight simulator, however it is also a really useful data presentation tool.
If you fancy using a more advanced GIS programme you could always sign up to use ESRI by clicking on the link below. ESRI are a international GIS company who supply geographical models to the armed forces, environment agency, and hundreds of other companies. They have an online interface which you can use known as arcGIS. Have a play.