The set of channels preconfigured in the Anaconda / Miniconda distributions. In short, packages built and distributed by Anaconda Inc.

A package that does not distribute files. It only specifies dependencies on other actual packages.

In conda speech, a metadata-only package exposed by the conda tooling to express hardware features as package constraints (e.g. supported CUDA versions). They always start with a double underscore.

An isolated Python installation that can coexist along other installations. They are usually activated on-demand whenever they are needed.

The authoritary source for conda packages. It consists of several channels, including defaults, conda-forge, bioconda and thousands more.

The Python Package Index. The main source for wheels and sdists. This is where pip usually downloads files from.