PyPI primarily hosts Python packages in the form of source archives, called "sdists", or of "wheels"[8] that may contain binary modules from a compiled language.

PyPI as an index allows users to search for packages by keywords or by filters against their metadata, such as free software license or compatibility with POSIX.

[13] A proposal to create a comprehensive centralised catalog, hosted at the python.org domain, was later finalized in November 2002.

[16] In May 2023 the Python Software Foundation reported that the United States Department of Justice had subpoenaed the user data of five PyPI contributors.

[17][18] A representative of the organization further explained that they expect privacy for contributors, but they also comply with the law and court orders, and for this reason turned over the data which the government requested.