Travelling waves are exactly what the name implies: waves that travel.
For example: you know how to wave at someone right?
Stand there and wave, do not move from the spot. That is a standing wave.
If you wave while you walk along, then that is a travelling wave.
More generally, a wave is anything loosely periodic — usually a displacement. If the periodic thing stays in the same place, then it is a standing wave. If the periodic thing changes position with time, then it is a travelling wave.
It is a movement of the pattern of movement.