.UDK File Extension
File TypeUnreal Engine Map File
What is a UDK file?
Game map design created by the Unreal Engine Development Kit (UDK), a popular free game engine developed by Epic Games; saves the layout, 3D objects, and textures used for a game map; used for creating the 3D worlds that games are played in.
UDK files can also contain locations of ambient sounds as well as pathing for artificial intelligence players.