make builds the module by copying the contents of <t>lib/ into blib ("build library"); if there are any XS modules, these get compiled at this point.

make test runs all the tests vs. the code now in blib to verify that it passes its tests.

make install copies the code in blib to the local Perl module directory as defined in the Perl install.

make disttest verifies that we have all the files we expect, we don't have any files we don't expect, and that they are all in the right relative locations when we ready the code for distribution; it also rechecks that the ready-for-distribution code still passes its tests.

make dist creates a tar ball of the source we want to distribute.