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.
Myst's gameplay is unusual among adventuring computer games in several ways. The player is provided with very little backstory at the beginning of the game, and no obvious goals or objectives are laid out. This means that players must simply begin to explore. There are no obvious enemies, no physical violence, and no threat of "dying" at any point, although it is possible to reach a few "losing" endings. There is no time limit to complete the game. The game unfolds at its own pace and is solved through a combination of patience, observation, and logical thinking.
It's an old but fun game if you like puzzles and logic games. Win95 or higher, just tested it today on my Vista machine, had to run in Win95 mode with 256 colors, but it played just great!