What is thermal expansion ? Write only its types.

Explanation

It is our common experience that most substances expand on heating and contract on cooling.
A change in the temperature of a body causes change in its dimensions. The increase in the dimensions of a body due to the increase in its temperature is called thermal expansion
There are three types of thermal expansion :
(a) Linear expansion : The expansion in length is called Linear expansion.
(b) Area expansion : The expansion in area is called Area expansion.
Volume expansion : The expansion in volume is called Volume expansion.
All are shown in the figure as below.