What is difference between Diffraction and Interference?

1. Interference happens when there are two waves that will intersect with each other. Interference can't happen with only one wave, diffraction can happen with only one wave.
2. Diffraction happens around edges or holes, interference happens at the intersection of two waves
3. Interference affects the waves. It can be either constructive or destructive. Diffraction does not affect the waves it only spreads or turn aroud
4. Interference does not contribute a lot in practical applications. it is mostly avoided especially when sound waves are concerned. Diffraction is very helpful. Because of it we can hear even if we are behind the tree or a wall
Regards,
Nirmal Singh
Askiitians faculty