On Unix (and Mac OS X, which is also Unix-based), it also depends on whether the module distribution being installed is pure Python or contains extensions (“non-pure”): stand for the directories that Python is installed to, and where it finds its libraries at run-time.
They are always the same under Windows, and very often the same under Unix and Mac OS X.
You don’t need to run Python or a setup script, you don’t need to compile anything—you might not even need to read any instructions (although it’s always a good idea to do so anyway). You might be interested in a module distribution that doesn’t have an easy-to-use installer for your platform.
This is particularly helpful when the build and install will be done by different users—for example, you might want to build a module distribution and hand it off to a system administrator for installation (or do it yourself, with super-user privileges).
For example, you can build everything in one step, and then install everything in a second step, by invoking the setup script twice: directory is up-to-date.
If a module distribution contains any extensions (modules written in C/C ), then the second form, with two ) directory contains all Python modules (pure Python and extensions) that will be installed.
In the future, more directories will be added to handle Python scripts, documentation, binary executables, and whatever else is needed to handle the job of installing Python modules and applications.
the top-level subdirectory that the module source distribution unpacks into.