This system is known as BSD, and it was developed at UC Berkeley. It was non-free in the 80s, but became free in the early 90s. A free operating system that exists today is almost certainly either a variant of the GNU system, or a kind of BSD system.
Ang sistemang ito ay kinilalang BSD, at nadebelop ito sa UC Berkeley. Hindi ito libre noong mga taon ng 1980, pero naging libre na noong mga unang taon ng 1990. Ang isang libreng operating system sa kasalukuyan ay halos tiyak na alinman sa mula sa o variant ng sistemang GNU o isang uri ng sistemang BSD.