gmake -f Makefile.global.
make -f makefile_name target
If you don't specify -f option and makefile_name the default will be
Makefile. target is one of the rule you specify within makefile, by default it's
Anyway I think Mike is right: in both cases you've downloaded a binary distribution so you don't need to compile it, it's already done. Go to the next step.
Makefile.global in 3.2 is only there as a makefile template for module writers.