There are two ways in which modules can be compiled and linked to
Apache - statically, or as a DSO (Dynamic Shared Object).
DSO is a more popular approach nowadays and is the recommended
one for mod_python. The module gets compiled as a shared library which
is dynamically loaded by the server at run time.
The advantage of DSO is that a module can be installed without
recompiling Apache and used as needed. A more detailed description of
the Apache DSO mechanism is available at
http://httpd.apache.org/docs-2.0/dso.html.
At this time only DSO is supported by mod_python.
Static linking is an older approach. With dynamic linking
available on most platforms it is used less and less. The main
drawback is that it entails recompiling Apache, which in many
instances is not a favorable option.