Why would you use a wave deformer

I’ve seen the wave deformer and read about setting it up but I’m not sure why or what this deformer is good for. Can someone enlighten me to how this could be used and an example or two?

There is a bone deformer used for rigid structures such as bones
or mechanical things. There is also a curve deformers used for tails,
snakes or rubber-jointed animation style characters. Finally there
is an envelope deformer used for enclosing areas to be deformed
such as faces or areas containing textures.

There is nothing in the software called a wave deformer that I am
aware of. Where did you come across this term?

I believe he is referring to the Deformation Wave Node:

http://docs.toonboom.com/help/harmony-14/premium/reference/node/deformation/deformation-wave-node.html

Off the top of my head I’d say it could be used to animate the silhouette of water waves or maybe a sine wave pattern.

I have not played around with it but if the wave form can be rounded as it appears to be used in the following video you could use it to recreate the pulse of energy that Popeye gets after swallowing a can of spinach.

Towards the end of this video it is being used for the elephant trunk exhaust:

https://www.youtube.com/watch?v=wPDzsUpkn8U&feature=youtu.be&list=PLC43A046ED952EC41&t=2626

Thanks for clarifying, I completely forgot this even exists.