The two types of wave interference are constructive and destructive.
These both describe what happens when waves combine
Constructive interference is when 2 waves combine to form a wave with a larger amplitude, but this is only if both waves are both positive or both negative.
Destructive interference is when the two waves are opposite, one is negative, one is positive. They subtract forming the combined wave that has a lower amplitude.
I hope that helps u out!! :)
