What is the technology that produces waves that when they intersect they produce heat?

I think they are currently used in the medical industry but can't remember the name of the technology.What is the technology that produces waves that when they intersect they produce heat?
sound might under the right conditions.



remember the wave of anything does have energy but unless and until the energy is deposited it willnot turen toheat.. the wave will "keep going"



example the breaking wave wrms the beach but not the water in the oceanWhat is the technology that produces waves that when they intersect they produce heat?
Sounds like a microwave...

oil change

chevys