A popular and free version of the
UNIX operating system that runs on
x86-compatible, DEC Alpha, PC-98, AMD64, IA64 and SPARC64 architectures. FreeBSD is distributed in
executable and
source code form. The source code enables ambitious users to actually extend the
operating system.
Another popular and free version of UNIX is Linux.
Learn more about
Open Source in Webopedia's "Did
You Know...?" section.