What is Mohorovicic Discontinuity and how was it discovered?

Hint: The interior of the Earth is made of various types of materials. Every one of those materials is not quite the same as one another by their physical and substance properties. Every layer is isolated from one another through a change zone. These change zones are called discontinuities.

Complete answer: The Mohorovicic Discontinuity is the limit between the crust and mantle of our planet. It was found by the refraction of seismic waves passing from one layer to the next.

While considering the earth tremor waves after a quake in 1909, Andrija Mohorovicic noticed that the earthquake waves were refracted at a specific profundity outside of the earth. Mohorovicic concluded from this perception that there was a sharp change in the structure of the earth at the point where the quake waves were refracted. His derivations lead to the possibility of the interior of the earth being isolated into the crust and the mantle. The line where the covering and the mantle meet is known as the Mohorovicic Discontinuity named after Andrija Mohorovicic who found the adjustment in the world's structure.

Note: There are five discontinuities inside the earth namely-
1- Conrad Discontinuity This is a transition zone among SIAL and SIMA.
2- Mohorovicic Discontinuity: This is a transition zone between the lower Crust and upper Mantle.
3- Repetti Discontinuity: This is a transition zone between Outer mantle and Inner mantle.
4- Gutenberg Discontinuity: This is a transition zone between the lower part of the Mantle and the outer Core.
5- Lehmann Discontinuity: This is a transition zone between the Outer core and Inner core.