The UNIX system family tree ------------------------------------------------------------------------------- First Edition (V1) | Second Edition (V2) | Third Edition (V3) | Fourth Edition (V4) | Fifth Edition (V5) | Sixth Edition (V6) ---------------------* / \ | / \ | / \ | Seventh Edition (V7) | / \ | / \ 1BSD SYSTEM I--------------* *--------------32V | | \ 2BSD---------------* SYSTEM II \ / | | \ / | SYSTEM III \/ | | 3BSD | SYSTEM IV | | | ...................... 4.0BSD 2.7.9BSD Mach 2 <---------------- SYSTEM V . | | | | \ Sun OS 1 4.1BSD --------------> 2.8BSD Mach 2.5 SVR I \ . | | (SCO/MS) | | \ . 4.1aBSD -----------\ | | | SVR II OSF/2 ....Sun OS 4.x | \ | XENIX 1.0 | | | . 4.1bBSD \ | | | SVR III | . | \ | XENIX 2.0 | / | | . *------ 4.1cBSD --------------> 2.9BSD | | / | | X / | | SCO SVR 3.2 <-----|---+--------> SVR 3.2 | | . Eighth Edition | 2.9BSD-Seismo | | | | | | . | | | SCO OpenDesktop 2 | +------------+--> AT&T SVR 4 <----|----------------------------+----<--- 4.2BSD 2.9.1BSD | | | | | . | | | SCO OpenDesktop 3 | | + | . +----<--- 4.3BSD -------------> 2.10BSD | | +--------|-----SVR 4.2----+---|--------+ | | / | | | | | + | | | | | / | SCO OpenServer 5 | Unixware2 AIX 3 | | | Solaris 2 Ninth Edition | / 2.10.1BSD | | (Novell) (IBM) | | | | | 4.3BSD Tahoe-----+ | | | | | O | | Solaris 2.x | | \ | | | | | t | | | | | \ | | | Unixware 7 AIX 4 h | | Solaris 7 v | 2.11BSD | | (SCO) | e | | | Tenth Edition | | | | | | r | | Solaris 8 | 2.11BSD rev #430 | | (SVR 5) | | | | | 4.3BSD NET/1 | | | | | & | | Solaris 9EA | v |---------------|----Unixware 8 | | | | 4.3BSD Reno | | | | | | V | OpenServer 5.06 | V | | V /*---------- 4.3BSD NET/2 -------------------+-------------* | | | | Ultrix 4 <.................* | | | | | | AIX 4.3.3 | (DEC) 386BSD 0.0 | | BSD/386 ALPHA V | | | | | | | | | | | Tru 64 5.x 386BSD 0.1 ------------>+ | BSD/386 0.3.[13] | V | (Compaq)---> | \ | 4.4BSD Alpha | | | | 386BSD 1.0 | | BSD/386 0.9.[34] + <...............................|..............................|....................|..................4.4BSD | . | . | | / | | Mach 3 (Base BSD) .....|............. | | 4.4BSD-Encumbered | | . . | . | NetBSD 0.8 | BSD/386 1.0 . HP-UX 8 | IRIX 4.x | | | | . ( HP ) | (SGI) FreeBSD 1.0 NetBSD 0.9 | BSD/386 1.1 ........*.......... . | . | | .----- 4.4BSD Lite | . . . | . FreeBSD 1.1 | / / | \ | Gnu Hurd 0.1 NeXT HP-UX 9 | IRIX 5.x | | / / | \ | . . . | . FreeBSD 1.1.5 .---|--------' / | \ | . @ . | . | / | / | \ | . + <- + ---------> + FreeBSD 1.1.5.1 / | / | \ | Gnu Hurd 0.2 | | | / NetBSD 1.0 <-' | \ | . HP-UX 10.x IRIX 6.0 | / | | \ | . | | FreeBSD 2.0 <--' | | BSD/OS 2.0 Gnu Hurd (H2) | | | \ | | . HP-UX 11.x IRIX 6.5.15 FreeBSD 2.0.5 \ | BSD/OS 2.0.1 . | | | .-----\------------- 4.4BSD Lite2 | . | | | | \ | | | | | V V V | | .-----|------Rhapsody | | | | | | | | NetBSD 1.3 | | | | | | | OpenBSD 2.3 | | | | | | BSD/OS 3.0 | FreeBSD 2.1 | | | | | | | | NetBSD 1.1 ------. BSD/OS 2.1 | FreeBSD 2.1.5 | | | \ | | | | | NetBSD 1.2 \ BSD/OS 3.0 | FreeBSD 2.1.6 | | | \ OpenBSD 2.0 | | | | | | \ | | | FreeBSD 2.1.6.1 | | | \ | | | | | | | \ | | | FreeBSD 2.1.7 | | | | | | | | | | | NetBSD 1.2.1 | | | FreeBSD 2.1.7.1 | | | | | | | | | | | | | | | | | *-FreeBSD 2.2 | | | | | | \ | | | | | | FreeBSD 2.2.1 | | | | | | | | | | | | | FreeBSD 2.2.2 | | | OpenBSD 2.1 | | | | | | | | | FreeBSD 2.2.5 | | | | | | | | | | OpenBSD 2.2 | | | | | NetBSD 1.3 | | | FreeBSD 2.2.6 | | | | | | | | | | | NetBSD 1.3.1 | BSD/OS 3.1 | | | | | | OpenBSD 2.3 | | | | | | NetBSD 1.3.2 | | | FreeBSD 2.2.7 | | | | | | | | | | | | | BSD/OS 4.0 | v | | | | | | | FreeBSD 2.2.8 | | | | | | | | | | | OpenBSD 2.4 | FreeBSD 3.0 <--------* | | v | | | | | NetBSD 1.3.3 | | *---FreeBSD 3.1 | | | | | | | | | BSD/OS 4.0.1 Linux 0.1 | FreeBSD 3.2----* | NetBSD 1.4 OpenBSD 2.5 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | FreeBSD 3.3 | | | | NetBSD 1.4.1 | | Linux 1.0 | | | | | | | OpenBSD 2.6 | | \ | FreeBSD 3.4 | | | | | | | | \ | | | | | | | | BSD/OS 4.1 Linux 1.0.x Linux 1.1.x FreeBSD 4.0 | | | | | NetBSD 1.4.2 | | | | | | | | | | | | | | | | | | | | | | | | |.......+ | FreeBSD 3.5 | | | | | OpenBSD 2.7 | | . | | | | | | | | | Linux 1.2.x . | FreeBSD 3.5.1 | | | | | | | | \ . | | | | | | | | | \. *---FreeBSD 4.1 | | | | | | | | Linux 1.3.x | | | | (?) | | | | | | | FreeBSD 4.1.1 | | / | | | | | | | | | | / | v | | |.......+ | FreeBSD 4.2 Darwin/ | NetBSD 1.4.3 | | | . | | Mac OS X | OpenBSD 2.8 BSD/OS 4.2 Linux 2.0.x . | | 10.0 NetBSD 1.5 | | | \ . | FreeBSD 4.3 | | | | v | \. | | | | v OpenBSD 2.9 | Linux 2.1.x | | | | NetBSD 1.5.1 | | | | | | | | | | | | FreeBSD 4.4 | | NetBSD 1.5.2 | |.......+ | | | | | | . | v | | | Linux 2.2.x . | | | | | \ . FreeBSD 5.0-current | NetBSD -current OpenBSD -current | \. | | | | | Linux 2.3.x v | v v | | Mac OS X Linux 2.4.x + 10.1 | \. 2.4.17 2.5.2 The UNIX system family tree ------------------------------------------------------------------------------- First Edition (V1) | Second Edition (V2) | Third Edition (V3) | Fourth Edition (V4) | Fifth Edition (V5) | Sixth Edition (V6) ---------------------* / \ | / \ | / \ | Seventh Edition (V7) | / \ | / \ 1BSD SYSTEM I--------------* *--------------32V | | \ 2BSD---------------* SYSTEM II \ / | | \ / | SYSTEM III \/ | | 3BSD | SYSTEM IV | | | ...................... 4.0BSD 2.7.9BSD Mach 2 <---------------- SYSTEM V . | | | | \ Sun OS 1 4.1BSD --------------> 2.8BSD Mach 2.5 SVR I \ . | | (SCO/MS) | | \ . 4.1aBSD -----------\ | | | SVR II OSF/2 ....Sun OS 4.x | \ | XENIX 1.0 | | | . 4.1bBSD \ | | | SVR III | . | \ | XENIX 2.0 | / | | . *------ 4.1cBSD --------------> 2.9BSD | | / | | X / | | SCO SVR 3.2 <-----|---+--------> SVR 3.2 | | . Eighth Edition | 2.9BSD-Seismo | | | | | | . | | | SCO OpenDesktop 2 | +------------+--> AT&T SVR 4 <----|----------------------------+----<--- 4.2BSD 2.9.1BSD | | | | | . | | | SCO OpenDesktop 3 | | + | . +----<--- 4.3BSD -------------> 2.10BSD | | +--------|-----SVR 4.2----+---|--------+ | | / | | | | | + | | | | | / | SCO OpenServer 5 | Unixware2 AIX 3 | | | Solaris 2 Ninth Edition | / 2.10.1BSD | | (Novell) (IBM) | | | | | 4.3BSD Tahoe-----+ | | | | | O | | Solaris 2.x | | \ | | | | | t | | | | | \ | | | Unixware 7 AIX 4 h | | Solaris 7 v | 2.11BSD | | (SCO) | e | | | Tenth Edition | | | | | | r | | Solaris 8 | 2.11BSD rev #430 | | (SVR 5) | | | | | 4.3BSD NET/1 | | | | | & | | Solaris 9EA | v |---------------|----Unixware 8 | | | | 4.3BSD Reno | | | | | | V | OpenServer 5.06 | V | | V /*---------- 4.3BSD NET/2 -------------------+-------------* | | | | Ultrix 4 <.................* | | | | | | AIX 4.3.3 | (DEC) 386BSD 0.0 | | BSD/386 ALPHA V | | | | | | | | | | | Tru 64 5.x 386BSD 0.1 ------------>+ | BSD/386 0.3.[13] | V | (Compaq)---> | \ | 4.4BSD Alpha | | | | 386BSD 1.0 | | BSD/386 0.9.[34] + <...............................|..............................|....................|..................4.4BSD | . | . | | / | | Mach 3 (Base BSD) .....|............. | | 4.4BSD-Encumbered | | . . | . | NetBSD 0.8 | BSD/386 1.0 . HP-UX 8 | IRIX 4.x | | | | . ( HP ) | (SGI) FreeBSD 1.0 NetBSD 0.9 | BSD/386 1.1 ........*.......... . | . | | .----- 4.4BSD Lite | . . . | . FreeBSD 1.1 | / / | \ | Gnu Hurd 0.1 NeXT HP-UX 9 | IRIX 5.x | | / / | \ | . . . | . FreeBSD 1.1.5 .---|--------' / | \ | . @ . | . | / | / | \ | . + <- + ---------> + FreeBSD 1.1.5.1 / | / | \ | Gnu Hurd 0.2 | | | / NetBSD 1.0 <-' | \ | . HP-UX 10.x IRIX 6.0 | / | | \ | . | | FreeBSD 2.0 <--' | | BSD/OS 2.0 Gnu Hurd (H2) | | | \ | | . HP-UX 11.x IRIX 6.5.15 FreeBSD 2.0.5 \ | BSD/OS 2.0.1 . | | | .-----\------------- 4.4BSD Lite2 | . | | | | \ | | | | | V V V | | .-----|------Rhapsody | | | | | | | | NetBSD 1.3 | | | | | | | OpenBSD 2.3 | | | | | | BSD/OS 3.0 | FreeBSD 2.1 | | | | | | | | NetBSD 1.1 ------. BSD/OS 2.1 | FreeBSD 2.1.5 | | | \ | | | | | NetBSD 1.2 \ BSD/OS 3.0 | FreeBSD 2.1.6 | | | \ OpenBSD 2.0 | | | | | | \ | | | FreeBSD 2.1.6.1 | | | \ | | | | | | | \ | | | FreeBSD 2.1.7 | | | | | | | | | | | NetBSD 1.2.1 | | | FreeBSD 2.1.7.1 | | | | | | | | | | | | | | | | | *-FreeBSD 2.2 | | | | | | \ | | | | | | FreeBSD 2.2.1 | | | | | | | | | | | | | FreeBSD 2.2.2 | | | OpenBSD 2.1 | | | | | | | | | FreeBSD 2.2.5 | | | | | | | | | | OpenBSD 2.2 | | | | | NetBSD 1.3 | | | FreeBSD 2.2.6 | | | | | | | | | | | NetBSD 1.3.1 | BSD/OS 3.1 | | | | | | OpenBSD 2.3 | | | | | | NetBSD 1.3.2 | | | FreeBSD 2.2.7 | | | | | | | | | | | | | BSD/OS 4.0 | v | | | | | | | FreeBSD 2.2.8 | | | | | | | | | | | OpenBSD 2.4 | FreeBSD 3.0 <--------* | | v | | | | | NetBSD 1.3.3 | | *---FreeBSD 3.1 | | | | | | | | | BSD/OS 4.0.1 Linux 0.1 | FreeBSD 3.2----* | NetBSD 1.4 OpenBSD 2.5 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | FreeBSD 3.3 | | | | NetBSD 1.4.1 | | Linux 1.0 | | | | | | | OpenBSD 2.6 | | \ | FreeBSD 3.4 | | | | | | | | \ | | | | | | | | BSD/OS 4.1 Linux 1.0.x Linux 1.1.x FreeBSD 4.0 | | | | | NetBSD 1.4.2 | | | | | | | | | | | | | | | | | | | | | | | | |.......+ | FreeBSD 3.5 | | | | | OpenBSD 2.7 | | . | | | | | | | | | Linux 1.2.x . | FreeBSD 3.5.1 | | | | | | | | \ . | | | | | | | | | \. *---FreeBSD 4.1 | | | | | | | | Linux 1.3.x | | | | (?) | | | | | | | FreeBSD 4.1.1 | | / | | | | | | | | | | / | v | | |.......+ | FreeBSD 4.2 Darwin/ | NetBSD 1.4.3 | | | . | | Mac OS X | OpenBSD 2.8 BSD/OS 4.2 Linux 2.0.x . | | 10.0 NetBSD 1.5 | | | \ . | FreeBSD 4.3 | | | | v | \. | | | | v OpenBSD 2.9 | Linux 2.1.x | | | | NetBSD 1.5.1 | | | | | | | | | | | | FreeBSD 4.4 | | NetBSD 1.5.2 | |.......+ | | | | | | . | v | | | Linux 2.2.x . | | | | | \ . FreeBSD 5.0-current | NetBSD -current OpenBSD -current | \. | | | | | Linux 2.3.x v | v v | | Mac OS X Linux 2.4.x + 10.1 | \. 2.4.17 2.5.2