World

•  internal world ID
  •  behavior_packs: Contains world behavior packs.
  •  db
    •  000005.ldb: Uneditable binary file.
    •  000006.log: Uneditable log file.
    •  region ID.dat^{[note 1]}
    •  CURRENT.dat: Contains file name of the "MANIFEST-<ID>" file.
    •  LOCK.dat​^{[more information needed]}
    •  MANIFEST-<ID>.dat
  •  level.dat
  •  level.dat_old: File that can be used as a backup for the other DAT file.
  •  levelname.txt: Contains the name of the world.
  •  resource_packs: Contains world resource packs.
  •  world_behavior_pack_history.json: Contains the UUID of all behavior packs that have ever been enabled for the world.
  •  world_behavior_packs.json: Determines which behavior packs stored in  development_behavior_packs are enabled for the world.
  •  world_icon.jpeg: The thumbnail of the world, which can be changed to an in-game screenshot in the edit world screen. Must be a 800x450 pixels JPEG file.
  •  world_resource_pack_history.json: Contains the UUID of all resource packs that have ever been enabled for the world.
  •  world_resource_packs.json: Determines which resource packs stored in  development_resource_packs are enabled for the world.

↑ The region ID is a 6-digit number. The region containing the player^[verify] is a .log instead of a .dat.

•  internal world ID
  •  manifest.json: Mandatory file, must specify "world_template" type. Contains the name and ID of the world. If the name and description are set to pack.name and pack.description, these will be assigned the texts specified in the localization files. Optionally, "allow_random_seed" : true can be added to the header to override seeds stored in the world data and generate a new world with a random seed.
  •  texts
    •  languages.json: Specifies all languages used.
    •  languagecode_COUNTRYCODE.lang: A language file for localization. Multiple language files can be used.

The in-game name and description of the world template can be changed for any language. The LANG file should contain pack.name= followed by the name of the template, and pack.description= followed by the description. languages.json should contain an array of all language codes used.

A finished world template can be zipped and packaged as a .mctemplate file. Opening this file will automatically import it as a world template, stored in com.mojang/world_templates. World templates can also be imported on Windows in the "Create from..." screen opened after pressing the "Create new world" button in the play screen.

All imported world templates are shown in the "Create from" screen. Selecting a world template will show the description, and opening it will open the Create New World screen with all data from the world template. Even though it may contain saved chunks and player data, the world seed (if "allow_random_seed" : true) can be changed, which may result in a sharp boundary between the saved chunks and newly generated chunks. Furthermore, Hardcore can be toggled again, allowing to revive dead players. Various game settings can be locked using lock_template_options, which requires to confirm a warning before one can change them.

World templates can also be purchased from the Marketplace. A list of Marketplace and Marketplace Pass world templates is shown in the "Create from..." screen, which can create a world similar to custom world templates.

In a world template, the base_game_version can be set to any minor release after 1.13.0. When set to an older version, the world will be created without vanilla resource and behavior packs from higher versions. In other words: the world is locked in an older version, features behave differently, have older looks, and new features are not available. Because the engine still runs on the latest version, unlike with backward-compatibility in Java Edition, certain features do behave differently from the actual game version. This includes hard-coded features outside resource and behavior packs, music, and various bugfixes, as well as features in the game that are not part of the world (such as menu screens).