Geographic information systems (GIS) (also known as Geospatial information systems) are computer software and hardware systems that enable users to capture, store, analyse and manage spatially referenced data. GISs have transformed the way spatial (geographic) data, relationships and patterns in the world are able to be interactively queried, processed, analysed, mapped, modelled, visualised, and displayed for an increasingly large range of users, for a multitude of purposes.
A GIS is not simply a computer system for creating maps. In fact, a map is simply the most common way of reporting information from a GIS database. A GIS is an “information system”. These systems are not just the software and hardware, but also, and most importantly, the collection of information (the database) about where geographic features (roads, buildings, fire hydrants, pipes, crime incidents, ponds, streams, etc.) are located in your community. Building this database involves compiling the information from maps and aerial photos, card files, people’s personal experience, or existing computer databases. A GIS database integrates all this information so that it can be used together and is accessible through a single computer, typically a personal computer (PC).