Nürnberg subway system represented with lines [Source]

GIS data is what makes a GIS map more than a simple reference map. Data expands the richness of a map: giving the user a deeper, more insightful view of an area or project.
As a category, GIS data is quite broad, with considerable variation in terms of:
- GIS data types
- File formats and extensions
- Data capture methods
- Use cases for the data
Remember, as a concept, GIS can be defined as the intersection of data and location.
Just jumping in? Check out part one: What is GIS?