Apple’s Mac operating system has undergone many sizeable changes over the years. Here’s every version in order, from the ...

Those contract stipulations enabled Microsoft to license the operating system generically as “MS-DOS” to “clone” PC manufacturers, according to Ruffer and Waldman, and Henderson. Axelrod notes that in ...

The computer's master control program. When a computer is turned on, a small "boot program" loads the operating system. Although additional system modules may be loaded as needed, the main part ...