Many mini-maps make use of similar features. Common features are:
Fog of war
In many games using a mini-map, the mini-map begins completely blank, while the map is automatically drawn as the player discovers new areas of the game world. After players discover new areas, the terrain of the discovered area often remains visible on the mini-map. If the player's characters or units cease being able to see the area, the area might be covered by a fog of war, so that unit or structure movements in that area will not be shown. Things in a fog of war portion of a mini-map may not be updated until they are rediscovered.
Similar to custom layers in Google Earth, some team-oriented multi-player games, such as Age of Empires II or Empire Earth, allow players to draw temporary lines, signals or markings on the mini-map for others to see. This allows for quick communication over large distances in games.
Rotation and zoom
In some 3D video games the mini-map rotates when the player character or game camera faces different directions, to keep the top of the map always corresponding to forward from the cameras point of view. This is common for games in the Grand Theft Auto series, and many racing games which show the track in a mini-map. Other games such as many in The Legend of Zelda series, the map does not rotate but features an arrow that moves about and rotates to show the position of the player character and the direction they're facing. In some games mini-maps that only show the close surrounding area often have icons on the edge to show the direction of locations or characters that are outside of the area shown on the map. Some games also have a feature where the mini-map zooms out when the player character is travelling at high speed, and zooms back in when they slow down.