Allow and Deny

Allow and deny are blocks that can be used to create restricted building areas or areas where players can build.[1]

Allow and deny blocks can either be obtained by using the pick block control, or by using various commands, such as /give, or the Creative inventory‌[Minecraft Education only].

When placed, allow blocks let players without world builder status place or destroy blocks in the area above them if immutable world is on, while deny blocks prohibit players without world builder, and their agents, from placing or destroying blocks in the area above them. This area covers an infinite distance above the block but does not cover the area below the block. If two allow or deny blocks are placed on top of one another, the block that is highest takes precedence. The deny block does not prevent the placing of blocks through commands, endermen, or pistons. They also do not prevent the placing of entities such as boats.