Minecraft chunk format
From Just Solve the File Format Problem
Minecraft chunk format is a data format used in the Minecraft game, as part of level formats such as the Minecraft Anvil format and the Minecraft Region format. This and other Minecraft formats are extensively documented in the Minecraft Gamepedia wiki.
A chunk expresses the content of a 16×256×16 region. They are stored using the Minecraft NBT format.
