.map

Game map created for Half-Life, a first-person shooter (FPS) video game; built using the Valve Hammer Editor; saved in a human-readable text-based format; may also be used for creating Quake and Quake II maps.

Valve Hammer Editor 4 saves map files in the newer .VMF format.

The Valve Hammer Editor was previously called "Worldcraft;" it is now commonly referred to "Hammer."