Question:What is a wave?
A Wave is a repeating vibration or oscillation that travels from the source of the vibration outwards.
A wave transports energy from one place to another.
When a wave travels through a material, the material moves backwards and forwards about its undisturbed position (oscillates or vibrates) BUT the material itself does not travel along with the wave.
This can be seen by watching a section of a string as a wave moves along it. The dot on the diagram indicates the centre of a piece of a string. Notice that this position in the string moves only up and down while the wave moves to the left. You know this already because when you make waves on a string both ends are held still, so the material cannot actually go anywhere.
A wave transports only energy from one place to another, not material.
If only one vibration is travelling then we call it a Pulse. If the vibration does not move and is not repeated then it is not a wave.