"It's a testament to the genius of unix design that a 39 year
old operating system is so prevalent in 2009. Unix introduced so
many operating system features we take for granted that they aren't
worth enumerating. Suffice it to say that all operating systems
have taken some degree of inspiration from unix.
"I am certain that someday some clever group of young developers
will create an operating system that is just as revolutionary as
unix was in 1970. Maybe not in my lifetime, and it's very likely
that 20 years from now I will still be cd-ing and ls-ing my way
around a unix shell prompt. For now, the perfect underlying os is
still some flavor of unix."