Air

Air is the block present in otherwise empty space.

Cave air '('only in Java Edition) is the underground air found in some generated structures and in caves.

Void air‌ (only in Java Edition) is used internally for blocks above (Y>255) and below (Y<0) the world, and in unloaded chunks.

Natural generation
Most generated structures generate air. Air is also generated in any space not occupied by another block.

Structures above ground generate normal air (with the exception of exposed badlands abandoned mineshafts and surface ponds, which generate cave air), and underground structures generate cave air. Void air is used in place of unloaded chunks and above or below the world's buildable area.

Obtaining
Air cannot be kept in the inventory and can be destroyed or created only by the placement or removal of other blocks respectively, although it is suggested by the /give command.

Air can be selected in the creation of worlds tab in Legacy Console Edition.

Usage
Air shares some properties with non-solid blocks, including allowing the player or mob to move within that space without suffocating, and also to catch their breath if they are drowning in water.

Air can be visualized with the use of structure blocks in save mode. With "Show invisible blocks" enabled, air is represented as small blue cubes.

Cave air and void air have no special properties; they are functionally the same as normal air.

ID[edit]
Java Edition: Bedrock Edition:

Issues
Issues relating to "Air" are maintained on the bug tracker. Report issues there.