Question

what is reflection and refraction

Answer 1

Reflection :--
The bouncing back of the light rays in the same medium is called reflection.
Refraction :--
The passing of light rays from one medium to another is called refraction.

Answer 2

Reflection - reflection is the change in direction of wavefront at an interface between two different media so that wavefront returns into the medium from which it originated is called reflection.

Refraction - refraction is change in direction of waves propagation due to change in its transmission medium is called refraction.