The public wants to access particular information about your house or neighborhood we point them to gis. Gis is a combination of maps and data. Not a graphic you see on a screen. You get the traffic for the streets the number of crimes for a Police District in a period of time. If the idea of combining the different layerce of information and stacking them on top of each other to present to the public. Other types of gis are web based Mapping Systems. Like google earth, yahoo maps. Microsoft. Those are examples of on line Mapping Systems that can be used to find businesses or get driving directions or check on traffic conditions. All digital maps. Gis is used in the city of San Francisco to better support what departments do. You imagine all the various elements of a city including parcels and the Critical Infrastructure where the storm drains are. The city access like the traffic lights and fire hydrants. Anything you is represent in a geo graphic space with be stored for retrieval an