Myst is a graphic adventure puzzle video game designed and directed by the brothers Robyn and Rand Miller. It was developed by Cyan (now Cyan Worlds) and published by Broderbund. The Millers began working on Myst in 1991 and released it for the Mac OS computer on September 24, 1993; it was developer Cyan's largest project to date. Remakes and ports of the game have been released for Sega Saturn, PlayStation, 3DO, Microsoft Windows, Atari Jaguar CD, CD-i, AmigaOS, PlayStation Portable, Nintendo DS, iOS, and Nintendo 3DS. Myst puts the player in the role of the Stranger, who uses a special book to travel to the island of Myst. There, the player uses other special books written by an artisan and explorer named Atrus to travel to several worlds known as "Ages". Clues found in each of these Ages help to reveal the back-story of the game's characters. The game has several endings, depending on the course of action the player takes. Upon release, Myst was a surprise hit, with critics lauding the ability of the game to immerse players in the fictional world. The game was the best-selling PC game until The Sims exceeded its sales in 2002. Myst helped drive adoption of the then-nascent CD-ROM format. Myst's success spawned four direct video game sequels as well as several spin-off games and novels.