Time Zone is a multi-disk graphical adventure game written and directed by Roberta Williams for the Apple II. Developed in 1981 and released in 1982 by On-Line Systems (later Sierra Entertainment), the game was shipped with six double-sided floppy disks and contained 1,500 areas (screens) to explore along with 39 scenarios to solve. Produced at a time when most games rarely took up more than one side of a floppy, Time Zone is one of the first games of this magnitude released for home computer systems.