Myst is a graphic adventure video game designed and directed by the brothers Robyn and Rand Miller. It was developed by Cyan (now Cyan Worlds), a studio based in Spokane, Washington, and was published by Brøderbund. The Millers began working on Myst in 1991, Cyan's largest project to date, and released it for the Macintosh computer in 1993. 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 worlds known as "Ages". Clues found in each Age help to reveal the back-story of the game's characters. The game has several endings, depending on the player's course of action. On release, Myst was a surprise hit, with critics lauding its ability to immerse the player in a fictional world. The game was the best-selling PC game of all time—until The Sims exceeded its sales in 2002—and helped to drive the adoption of the then-nascent CD-ROM format. Myst's success spawned four direct video-game sequels and several spin-off games and novels.