What is diffraction ? Who discovered it? What kind of diffraction phenomenon occurs in waves ?

Explanation

The phenomenon of waves around the opaque (obstacle) is called diffraction.
Accurate definition of diffraction : Diffraction is the physical effect produced by the limited part of the wavefront
Diffraction was first discovered by a scientist named Grimaldy.
Diffraction phenomenon occur in sound waves, light waves, water waves or matter waves.
Diffraction depends on the wavelength of wave `lamda` and width of slit d. That is on the ratio `(lamda)/(d)`.
Due to the diffraction phenomenon that occurs simultaneously in the dark and bright area near the geometric shadow of opaque object
Our eyes or optical devices such as telescopes and microscope seem to have a limit on resolving power due to diffraction.
The colours appearing on the CD are actually due to the diffraction effects.
The true understanding of diffraction can only be explained by wave theory. There are two types of diffraction that are obtained from the waves that incident on the slit.
(i) If the spherical wavefronts incident on the slit, then the diffraction called Fresne diffraction.
(ii) If the plane wavefronts incident on the slit then the diffraction called Fraunhoffe: diffraction.