ABSTRACT
Geographic information systems arose in the 1970s as a coming together of several projects, each applying digital geographic data to specific ends. The parlous state of information technology at the time forced the developers of GIS to adopt various assumptions and shortcuts, some of which are still with us. Many developments since the 1970s have vastly expanded the scope of GIS, allowed it to become a means of communicating knowledge of the planet through the Internet, and moved it from the domain of experts and professionals to the general public.
