Chapter 8. Logfile Geo-visualizer
In the middle of the 19th century, a cholera outbreak occurred in London. A physician named John Snow drew a point on every location of a case he heard about on a map. Using this map, he could locate the source of the outbreak in a street water pump. He then removed the handle of the pump to terminate the cholera outbreak. This was one of the earliest known geographic information systems (GIS). Today, these are created using vector maps or satellite images and geocoded data.
