When developing with Python within the ArcGIS platform, you have two options, ArcPy, and/or the ArcGIS API for Python

arcpy

ArcPy is a Python site package that provides a useful and productive way to perform geographic data analysis, data conversion, data management, and map automation with Python.

This package provides a rich and native Python experience offering code completion (type a keyword and a dot to get a pop-up list of properties and methods supported by that keyword; select one to insert it) and reference documentation for each function, module, and class.

For more information, visit the Homepage.

api

The ArcGIS API for Python is a powerful, modern and easy to use Pythonic library to perform GIS visualization and analysis, spatial data management and GIS system administration tasks that can run both in an interactive fashion, as well as using scripts.

It enables power users, system administrators and developers to leverage the rich SciPy ecosystem for automating their workflows and performing repetitive tasks using scripts. It integrates well with the Jupyter Notebook and enables academics, data scientists, GIS analysts and visualization enthusiasts to share geo-enriched literate programs and reproducible research with others.

For more information, visit the Homepage.

misc

For any other Python scripts that may not be directly related to ArcGIS, but are helpful across the framework.