4.2. History of Linux (Part Two)

• As source was available, Unix evolved fast and diversified.
  -> AT&T Unix, BSD (Berkeley Unix), Ultrix (DEC), AIX (IBM), Solaris (Sun), HP-UX (HP), Xenix (Microsoft), etc.

• Andrew Tanenbaum rewrote a Unix kernel for his OS classes for IBM PCs
  -> Minix (also Copyrighted)

• Linus Torvalds (as a second year student in 1991) used Minix as a model for a Unix kernel for Intel 286 CPUs (first Intel CPU with MMU features)
  -> Linux

• No Minix code was used. Torvalds chose the GPL (GNU Public License)