How does light travel through air?

Answer 1

Light travels as an electromagnetic wave radiation, along with other radiation like radio and TV waves, microwaves, UV, and so on. All these are basically the same but have different frequencies. Air does not absorb light much, it is almost transparent to light unless it contains dust etc, so there is no reason why it should not travel through air. But don't confuse it with sound, sound is a compression wave in the air and is quite different to light in the way it travels.

Answer 2

In the same way how it does though the vacuum. The air atmosphere is considered as an ideal gas it means the distance between its molecules is very big relatively to molecule sizes. Basically it's enough for the light to travel. Light does get absorbed by the air molecules but it changes only the light speed (it's a well-know fact that that light in media travels with a different speed than in the vacuum) the behavior of the light stays the same as the vacuum. As result light can described in different medias using the same set of equations but using different media constants (refractive index, dielectric constant and so).

answer 2 Light is an electromagnetic wave, just as are radio waves, and x-rays. It does not need a medium through which to travel, it travels because the Electric component induces a Magnetic wave, and the Magnetic wave induces an Electric one.