Information:

Players always have to walk on the ground and swim to explore their world. The air has always been off-limits to players, unless they went into creative mode. Not anymore.

The art of movement through the air have been showcased in many different ways by several people. In their videos they used flying carpets, jetpacks or flying machines. Some of the concepts were really glitchy, and sometimes hard to create.

This concept is not that hard to create, and it also takes the art of movement through the air to another level.

List of commands:

> execute @e[type=Player] ~ ~ ~ testforblock ~ ~-1 ~ air

> execute @e[type=Player] ~ ~ ~ setblock ~ ~-1 ~ barrier

> execute @e[type=Player] ~ ~ ~ fill ~1 ~-2 ~1 ~-1 ~-2 ~-1 air 0 replace barrier

World download:

> http://www.planetminecraft.com/project/concept-air-walking/

README:

> I do not know if I am the first one to discover this concept, so please do not get mad if you have published a similar concept.
> If you make a video or tutorial using this specific concept please credit me and include a link to this post. Do not claim this idea as your own.
> You are free to use this concept in your maps as you wish. Crediting me for this concept in your maps is not required.
> This concept can only be used in the 1.8 snapshots.