ArcGIS Pro uses the concept of a Geographic Information System (GIS) to build maps in which each category of spatial feature is a separate layer. The layers are spatially "georeferenced" so when the user overlays them the program can line them up correctly to build and symbolize a map or analyze relationships between them.
The first three types of layers listed below are called "vector layers" or "feature layers" and contain individual features that the program can distinguish.
Point (e.g., landmarks, cities on a small-scale map). Zero-dimensional.
Line, or arc (e.g., roads, streams, railroads, power lines). One-dimensional.
Polygon (e.g., political entities, census geographies such as tracts). Two-dimensional.
Raster images (e.g., an aerial photograph, scanned topographic map, or remote sensing imagery such as elevation data). Contrasting with feature-based vector layer, these are images based on an X by Y grid of cells, each of which has a value that represents something like elevation, land use classification, or color value.
Data is associated with the spatial features, and can be mapped or analyzed:
There can be attributes, or tabular data, associated with each feature in a layer (e.g., demographic data for each Census Tract).
Join your own data: Data tables (e.g., database or spreadsheet files) can be added ("joined") to a layer if there is a field with common values (e.g., census tract number).
Plot XY data: The program can also map data files in some spreadsheet and database formats if some fields contain geographic coordinates).
Geocode addresses: Tables that contain address data can be "geocoded" to map the locations address locator reference files.
Georeference images: Users can open a non-referenced raster image and georeference it in ArcGIS Pro, and sometimes can vectorize features from a raster image.
You can also add your own information to a map with drawing and writing tools.
