This is a resource for educators interested in utilizing mapping and Geographic Information Systems (GIS) in their curriculum. The ubiquity of modern mapping technologies and their applications across science and society justifies the need to introduce students to this powerful tool for understanding and exploring our world. While not exhaustive, this site contains information and links to resources for learning and teaching GIS and mapping. It is focused on data related to North Carolina but should be applicable to anyone interested in mapping.
A GIS is a computer program for creating, editing, analyzing, and visualizing spatial data. Any information that has a spatial context (state borders, streams, tweets, etc.) can be used in GIS.
There are many GIS applications available, some open source and some proprietary. Below is a list of a few popular programs:
There are two main types of digital map data: vector data and raster data.
Vector data represents geographic data as geometric coordinates (x and y position). A vector data set can consist of either points (one coordinate), lines (two or more connected, open coordinates), or polygons (three or more connected, closed coordinates).
The most common type of vector data used in GIS is the shapefile. A shapefile is not one file but actually a collection of several files. There are three mandatory files that describe the geometry of the shapefile (.shp), the tabular data associated with the shapefile (.dbf), and an index for moving through the shapefile (.shx), though more may be present (.prj, .shp.xml, .sbn, .sbx, etc.). These files must be kept together in the same directory. When adding a shapefile to a GIS you will load in the file with the .shp extension
Raster Data is in the form of cells in a grid. Each cell in the grid represents one or more pieces of information (e.g., elevation, color, rainfall, etc.). A photo of Earth from a satellite is an example. If you zoom in close enough you can see the individual pixels (cells) from the image.
There are many raster data formats. A common type is the geoTIFF, a georeferenced image file. Aerial photographs, digital elevation models (DEMs), and land use and land cover are examples of raster data.
There are numerous online resources for accessing GIS data. Below are a few helpful sites with free data: