The following section assumes that there is a C-compiler installed on your system, in particular the GNU project C-compiler, gcc, which is a common resource on many Linux and Unix systems. If this compiler is not installed on your system, it may be downloaded from the GNU gcc website http://gcc.gnu.org/. If your system has a ``native'' C-compiler installed (this may be the case for SUN or DEC systems, for instance), then this compiler may be employed instead of gcc, but read the entirety of the next section before you attempt compilation. If you have gcc on your Mac computer, you should be able to follow the UNIX/Linux instructions.