Huygen’s principle and refraction?

Question

Could someone explain in words(no need to go too deep only need the basics) and not in maths how refraction occurs due to a change of wave speed as the wave moves from one medium to another.

Answer 1

How about no words? Check out:

http://www.walter-fendt.de/ph14e/huygenspr.htm

Essentially every point on the wavefront can be considered an isotropic source. Using the different speed of light in a medium produces the bending due to diffraction.

Answer 2

Put a pencil in a clear glass of water. The light just moves slower because water is less dense than air. Hence, refraction.