What is GIS?
GIS stands for Geographic Information Systems. It is a tool that combines the power of maps, computers, drawing tools, and information databases into one interactive system that people use to study and analyze geographical patterns and events.
The key to understanding GIS is in the very first letter - the G, for Geographic. Geography is the study of the earth, its physical features, and the living things (including humans) that inhabit the globe. Geography also strives to understand the impact of location on living things and their creations, as well as the impact of living things and their creations on the places they inhabit.
Relationships that are based on geographical features are called spatial relationships. Examples of spatial relationships are size, shape, distance, proximity, position and location. Things are also spatially related to each other if they are connected, are next to each other, or on opposite sides of the globe, or if they overlap, intersect, or are contained within some area or boundary.
Pictured at right is an aerial photograph of Beaver Stadium, the home of the Penn State football team, located in State College, Pennsylvania. As you can see just by looking, it is chocked full of spatial features and relationships. Some examples are below.
stadium, playing field, parking lots, undeveloped areas, and other
visible buildings are all different sizes, shapes,
and dimensions. They also vary in how far apart
they are, and how close they are to roads and intersections.
Each road varies in their length, width, distance to other roads and intersections, and the direction they travel in.
element in this image ( structures, land masses, and roads ) has
a unique set of geographic coordinates and a unique location. More
than anything else, this is the heart of GIS's power - the capacity
to connect each and every one of these geographic coordinates to
the environmental, political, agricultural, commercial, medical,
historical, and cultural events and phenomena which define these