Quake Army Knife (QuArK) is a multi-purpose tool for the games using engines similar to or based on the Quake engine by id Software. QuArK has the ability to directly edit maps, and to a limited extent, models, and can import, export and convert sounds, textures and various other game assets.

It is also able to modify .pak and .pk3 files, as well as importing compiled BSP's in order to study the entities as well as add/change/delete entities from these files. No other game editing tool available has the ability to do all of these things.

QuArK was originally called QuakeMap, and was a map-only editor for Quake. QuakeMap broke with the "traditional" 3-view (xy, xz, yz) interface and opted to go for a much simpler to understand interface that showed just a "side" and "top" view, with a "compass" that rotated your level through 360 degrees, making the third "view" unnecessary.

This opened up much of the screen real estate, and by incorporating a small uncluttered toolbar on the left hand side, along with extensive right-click functionality, this enabled new users to quickly and easily learn the interface enough to put their efforts into their creations, and not into learning the editor and its complicated arrays of views and tool buttons.