Question

What is the difference between interferance and diffraction????

Answer 1

``Interference'' is the more general concept: it refers to the phenemenon of waves interacting. Waves will add constructively or destructively according to their phasedifference. ``Diffraction'' usually refers to the spreading wave pattern from a finite-width aperture

Answer 2

Hey !!

INTERFERENCE  

It is due to the superposition of two waves coming from two coherent sources.

The width of the interference bands is equal.

The intensity of all maxima ( fringes ) is same.

DIFFRACTION  

It is due to the superposition of secondary wavelets originating from different parts of the same wavefront.

The width of the diffraction bands is not the same.

The intensity of central maximum is minimum and goes on decreasing rapidly with increase in order of maxima.

Good luck !!