Unix 简史
1965年时，贝尔实验室(Bell Labs)加入一项由奇异电子(General Electric)和麻省理工学院(MIT)合作的计画；该计画要建立一套多使用者、多任务、多层次(multi-user、multi-processor、multi-level)的MULTICS操作系统。直到1969年，因MULTICS计画的工作进度太慢，该计画就被停了下来。当时，Ken Thompson（后被称为Unix之父）已经有一个称为「星际旅行」的程序在GE-635的机器上跑，但是反应非常的慢，正巧也被他发现了一部被闲置的PDP-7(Digital的主机)，Ken Thompson和Dernis Ritchie就将「星际旅行」的程序移植到PDP-7上。而这部PDP-7就此在整个计算机历史上留下了芳名。
MULTICS 其实是”MULTiplexed Information and Computing System”的缩写，在1970年时，那部PDP-7却只能支持两个使用者，当时，Brian Kernighan 就开玩笑地戏称他们的系统其实是：”UNiplexed Information and Computing System”，缩写为”UNICS”，后来，大家取其谐音，就称其为”Unix”了。1970年可称为是Unix元年。
1971年，他们申请了一部PDP-11/20，申请的名义是：要发展文书处理系统。该提案被获采纳，他们也发展出了一套文书处理系统 ─ 就是现在Unix操作系统里面文书处理系统(nroff/troff)的前身。有趣的是，没有多久，贝尔实验室的专利部门真的采用了这套系统作为他们处理文件的工具，而贝尔实验室的专利部门也就顺理成章地成为Unix的第一个正式使用者。当时，那部PDP-11／20只有0.5MB磁盘空间。而描述这整个系统的文件被标示为：”First Edition”，版本日期是1970年11月。从此以后，Unix的版本就以系统文件的版别来称呼。
UNIX家谱
UNIX的历史开始于1969年ken Thompson，Dennis Ritchie（即著名的K&G，C语言的发明人）与一群人在一部PDP-7上进行的一些工作，后来这个系统变成了UNIX。它主要的几个版本为：
V1（1971）：第一版的UNIX，以PDP-11/20的汇编语言写成。包括文件系统，fork、roff、ed等软件。
V4（1973）：以C语言从头写过，这使得UNIX修改容易，可以在几个月内移植到新的硬件平台上。最初C语言是为UNIX设计的，所以C与UNIX间有紧密的关系。
V6（1975）：第一个在贝尔实验室外（尤其是大学中）广为流传的UNIX版本。这也是UNIX分支的起点与广受欢迎的开始。1.xBSD （PDP-II）就是由这个版本衍生出来的。
V7（1979）：在许多UNIX玩家的心目中，这是“最后一个真正的UNIX，”这个版本包括一个完整的K&RC编译器，Bourne shell。V7移植到VAX机器后称为32V。
目前开发UNIX（System V）的公司是Unix System Laboratories (USL)。USL本为AT&T所有，1993年初被Novell收购。Novell于1993年末将UNIX这个注册商标转让给X/Open组织。
目前为止，UNIX有两大流派：那就是AT&T发布的UNIX操作系统System V与美国加州大学伯克利分校发布的UNIX版BSD（Berkeley Software Distribution）。SVR4是两大流派融合后的产物。1991年底，与System V针锋相对的开放软件基金会(Open Software Foundation)推出了OSF/1。
现在几种主要的UNIX版本：
* AIX：IBM的UNIX，是根据SVR2（最近已经出到SVR3.2）以及一部分BSD延伸而来，加上各种硬件的支持。具备特有的系统管理（SMIT）。
* 386BSD：Jolitz从Net/2 software移植过来的。支持Posix，32位。
* FreeBSD：1.x从386BSD 0.1而来，FreeBSD 2.x版是用4.4BSD lite改写。
* HP-UX（HP）：旧系统是从S III（SVRx）发展面来，现在是由SVR2（4.2BSD）发展而来，目前是10.x版。
* Linux(x86)：遵从POSIX，SYSV及BSD的扩展，这一点从上页表中即可看出。
* OSF/1（DEC）：DEC对OSF/1的移植。
* SCO UNIX（x86）：SVR3.2，目前影响较大的PC UNIX。
* SunOS（680×0，Sparc，i386）：根据4.3BSD，包含许多来自System V的东西。Sun的主要成果在于：NFS，OpenLook GUI标准，现演变为Solaris 。
* Ultrix(DEC)：根据4.2BSD再加上许多4.3BSD的东西。
* Xenix(x86)：Intel硬件平台上的UNIX，以SVR2为基础，由微软推出。在中国使用较广泛。
| Year | Event |
| 1957 | Bell Labs found they needed an operating system for their computer center which at the time was running various batch jobs. The BESYS operating system was created at Bell Labs to deal with these needs. |
| 1965 | Bell Labs was adopting third generation computer equipment and decided to join forces with General Electric and MIT to create Multics (Multiplexed Information and Computing Service). |
| 1969 | By April 1969, AT&T made a decision to withdraw Multics and go with GECOS. When Multics was withdrawn Ken Thompson and Dennis Ritchie needed to rewrite an operating system in order to play space travel on another smaller machine (a DEC PDP-7 [Programmed Data Processor 4K memory for user programs). The result was a system which a punning colleague called UNICS (UNiplexed Information and Computing Service)–an ’emasculated Multics’. |
| 1969 | Summer 1969 UNIX was developed. |
| 1969 | Linus Torvalds is born. |
| 1971 | First edition of UNIX released 11/03/1971. The first edition of the “UNIX PROGRAMMER’S MANUAL [by] K. Thompson [and] D. M. Ritchie” is also dated “November 3, 1971”. It includes over 60 commands like: b (compile B program); boot (reboot system); cat (concatenate files); chdir (change working directory); chmod (change access mode); chown (change owner); cp (copy file); ls (list directory contents); mv (move or rename file); roff (run off text); wc (get word count); who (who is one the system). The main thing missing was pipes. |
| 1972 | Second edition of UNIX released 12/06/1972 |
| 1972 | Ritchie rewrote B and called the new language C. |
| 1973 | UNIX had been installed on 16 sites (all within AT&T/Western Electric); it was publically unveiled at a conference in October. |
| 1973 | Third edition of UNIX released February 1973 |
| 1973 | Forth edition of UNIX released November 1973 |
| 1974 | Fifth edition of UNIX released June 1974 |
| 1974 | Thompson went to UC Berkeley to teach for a year, Bill Joy arrived as a new graduate student. Frustrated with ed, Joy developed a more featured editor em. |
| 1975 | Sixth edition of UNIX released May 1975 |
| 1975 | Bourne shell is introduced begins being added onto. |
| 1977 | 1BSD released late 1977 |
| 1978 | 2BSD released mid 1978 |
| 1979 | Seventh edition of UNIX released January 1979 |
| 1979 | 3BSD released late 1979 |
| 1979 | SCO founded by Doug and Larry Michels as UNIX porting and consulting company. |
| 1980 | 4.0BSD released October 1980 |
| 1982 | SGI introduces IRIX. |
| 1983 | SCO delivers its first packaged UNIX system called SCO XENIX System V for Intel 8086 and 8088 processor-based PCs. |
| 1984 | Ultrix 1.0 was released. |
| 1985 | Eighth edition of UNIX released February 1985 |
| 1985 | The GNU manifesto is published in the March 1985 issue of Dr. Dobb’s Journal. The GNU project starts a year and a half later. |
| 1986 | HP-UX 1.0 released. |
| 1986 | Ninth edition of UNIX released September 1986 |
| 1987 | Sun and AT&T lay the groundwork for business computing in the next decade with an alliance to develop UNIX System V Release 4. |
| 1988 | HP-UX 2.0 released. |
| 1988 | HP-UX 3.0 released. |
| 1989 | SCO ships SCO UNIX System V/386, the first volume commercial product licensed by AT&T to use the UNIX System trademark. |
| 1989 | HP-UX 7.0 released. |
| 1989 | Tenth edition of UNIX released October 1989 |
| 1990 | AIX short for Advanced Interactive eXecutive was first entered into the market by IBM February 1990. |
| 1991 | Sun unveils Solaris 2 operating environment, specially tuned for symetric multiprocessing. |
| 1991 | Linux is introduced by Linus Torvalds, a student in Finland. Who post to the comp.os.minix newsgroup with the words: Hello everybody out there using minix – I’m doing a (free) operating system (just a hobby, won’t be big and professional like gnu) for 386(486) AT clones. |
| 1991 | HP-UX 8.0 released. |
| 1991 | BSD/386 ALPHA First code released to people outside BSDI 12/xx/1991 |
| 1992 | HP-UX 9.0 released. |
| 1993 | NetBSD 0.8 released 04/20/1993 |
| 1993 | FreeBSD 1.0 released December of 1993 |
| 1994 | Red Hat Linux is introduced. |
| 1994 | Caldera, Inc was founded in 1994 by Ransom Love and Bryan Sparks. |
| 1994 | NetBSD 1.0 released 10/26/1994 |
| 1995 | FreeBSD 2.0 released 01/xx/1995 |
| 1995 | SCO acquires UNIX Systems source technology business from Novell Corporation (which had acquired it from AT&T’s UNIX System Laboratories). SCO also acquires UnixWare 2 operating system from Novell. |
| 1995 | HP-UX 10.0 released. |
| 1995 | 4.4 BSD Lite Release 2 the true final distribution from the CSRG 06/xx/1995 |
| 1997 | HP-UX 11.0 released. |
| 1997 | Caldera ships OpenLinux Standard 1.1 May 5, 1997, the second offering in Caldera’s OpenLinux product line |
| 1998 | IRIX 6.5 the fifth generation of SGI UNIX is released July 6, 1998. |
| 1998 | SCO delivers UnixWare 7 operating system. |
| 1998 | Sun Solaris 7 operating system released. |
| 1998 | FreeBSD 3.0 released 10/16/1998 |
| 2000 | FreeBSD 4.0 released 03/13/2000 |
| 2000 | Caldera Systems Inc. announces that Caldera Systems has entered into agreement to acquire the SCO Server Software Division and the Professional Services Division |
