- The document discusses the history and development of Linux operating systems, starting from early systems like DOS, Apple Macs, Unix, and MINIX. - It describes how Linus Torvalds began developing Linux in 1991 as a hobby, seeking feedback on his system which was similar to MINIX but free of MINIX code. Linux grew more robust over time with versions 0.01 to 0.02 etc. - Commercial vendors eventually supported Linux, porting it to many platforms, and popular Linux distributions emerged like Ubuntu, Fedora, etc. The document includes exchanges between Linus Torvalds and Andrew Tanenbaum debating Linux's design.

1. Mysterious ? Hard to use ? For Experts Only ?

6. Many Linux distributions: