Game level created by Minecraft, a single player or multiplayer first-person perspective game; contains information for a game map, including the location of 3D building blocks, spawn points, sky colors, and map size; stored in a proprietary tagged binary format called the Named Binary Tag format, or NBT for short.

Minecraft is a Java-based program that can be run in a Web browser. In Minecraft, users create and destroy blocks and mine resources in a 3D environment. NOTE: MCLEVEL files were used by early releases of Minecraft (called "indev") and are not compatible with current versions of the software. At the time MCLEVEL files were used, only registered users of Minecraft were able to save MCLEVEL files.