Theory:

Depending on the surface on which light hits, the reflection is classified into two types
  • Regular reflection
  • Diffused reflection
Regular reflection:
When parallel rays of light fall on a smooth surface, they are reflected as parallel rays. This is called regular reflection.
It is also called specular reflection.
4 (1).png
Light reflection by a smooth surface
 
In the above image, the reflecting surface is very smooth; so when parallel rays of light fall on it, it will reflect as parallel rays by obeying the laws of reflection. If the reflecting surface is smooth or regular, then we have a specular or regular reflection.
  
Diffused reflection:
When parallel rays of light fall upon an irregular or rough surface, they are reflected back into all directions or at different angles. This is called diffused reflection.
It is also called irregular reflection.
3.png
Light reflection by an irregular surface
 
In the above image, the reflecting surface is very rough, so when parallel rays of light fall on it, it will reflect at different angles by obeying law of reflection. Thus, the reflected rays are not the same as incident rays. If the reflecting surface is not smooth or rough, then we have diffused or irregular reflection.
 
Specular or regular reflectionDiffused or irregular reflection
Mirror_MET_141134.jpgdesert-5003439_1920.jpg
 
The mirror has a smooth surface in the above image, so regular or specular reflection occurs when light rays fall on it. Cracked land has a rough surface, so irregular or diffused reflection occurs when light rays fall on it.
 
Speed of light:
When we switch on a bulb in a dark room, light spreads the whole room quickly. This is because the speed of the light. Light travels three lakh kilometres per second in air or vacuum. Nothing can travel faster than light. Speed of light is denoted by the letter '\(c\)'
Speed of light (\(c\))= 3×108\(m/s\)
Reference:
https://pixabay.com/photos/desert-drought-dry-earth-arid-5003439/
https://commons.wikimedia.org/wiki/File:Mirror_MET_141134.jpg
https://pixabay.com/photos/ice-cubes-ice-water-cold-frozen-3506781/
https://commons.wikimedia.org/wiki/File:Porolon.jpg