Caption: An animation of a single transverse wave (a complete up-and-down cycle) propagating in one direction. The animation is generic for transverse waves, but it is NOT particularly good for illustrating electromagnetic waves (which are transverse waves).

Features:

1. Note that a wave form with a complete up-and-down cycle has a length called a wavelength. The universal symbol for wavelength is the small Greek lambda = λ.

2. In transverse waves, the propagation direction and oscillation direction are perpendicular.

3. In longitudinal waves, the propagation direction and oscillation direction are parallel.

4. There are, in fact, combinations of transverse waves and longitudinal waves: the most well known example is surface water waves.