A cikin 1977, Berkeley Software Rarraba (BSD) da aka ci gaba da Computer Systems Research Group (CSRG) daga UC Berkeley, bisa ga 6th edition na Unix daga AT & T. Tun BSD kunshe da Unix code cewa AT & T mallakar, AT & T gabatar da wani kara (USL v. BSDi) a farkon 1990s da Jami'ar California. Wannan karfi iyakance ci gaba da kuma tallafi na BSD. A 1983, Richard Stallman fara da GNU aikin da burin na samar da wani free UNIX-OS. A matsayin wani ɓangare na wannan aikin, ya rubuta da GNU Janar Jama'a License (GPL). By farkon 1990s, akwai kusan isa software don ƙirƙirar cikakken tsarin aiki. Duk da haka, da GNU kwaya, da ake kira Hurd, ya kasa jawo hankalin isa kokarin, barin GNU ci gaba. A 1985, Intel buga na farko 8038 x86 tare da wani 32-bit microprocessor management naúrar, da kuma a farkon 1986 da aka rufe da bayanin yadda za a fito da wannan software.
kusan isasshen software don ƙirƙirar cikakken tsarin aiki