Reflection

Reflection is a wave phenomenon where a wave bounces off a surface, returning into the same medium from which it emerged.
The angle of incidence is the angle between the incident (incoming) wave and the normal (an imaginary line drawn perpendicular to the surface).
The angle of reflection is the angle between the reflected wave and the normal.
According to the law of reflection, the angle of incidence is equal to the angle of reflection.
Reflection does not change the frequency of a wave but it may change its direction and phase.
There are two types of reflection: specular and diffuse.

Specular reflection occurs when a wave is reflected in a single direction. This happens when the wave encounters a smooth and even surface such as a mirror.
In specular reflection, the reflected image is a mirror image of the object emitting or reflecting the wave.
All parallel incident light waves are reflected in parallel, maintaining the details and sharpness of the original images.

Diffuse reflection occurs when a wave hits a rough or uneven surface and is reflected in many different directions.
In diffuse reflection, the rough surface causes the parallel incident rays to scatter and reflect at different angles.
This scattering of light causes the resulting image to be blurred or not recognisable as it does not maintain the coherent pattern of the incident light.
Most objects we see around us appear visible due to diffuse reflection.