A site-package created by Esri to expose ArcGIS for Desktop (and ArcGIS Pro) geoprocessing, mapping, etc, to Python.
A site-package created by Esri to perform geographic data analysis, data conversion, data management, and map automation with Python.
As of ArcGIS 10.1 it has five modules:
- Data Access (da)
- Mapping (mapping)
- Network Analyst (na)
- Spatial Analyst (sa)
- Time (time)