Adventure: Denotes any game where the emphasis is based on experiencing a story through the manipulation of one or more user-controlled characters and the environment they exist in. Gameplay mechanics emphasize decision over action.
Role-playing games (RPGs) are a common sub-genre of all adventure games, as are the classic Sierra "Quest" series of games. Text adventures (Interactive Fiction) are also, by definition, adventure games. Part of the Basic Genres category.
You can browse through games in the MobyGames database that are part of this genre via the game browser.