What is strain? List its types?

A strain is defined as the length change ratio to the original length when the load is applied. Based on the type of loading, a strain can be divided into three types.

Normal strain - Normal strain is measured by dividing the change in length by the original length. It tells the relative amount of deformation in the structure due to the force applied.

Shear Strain - It is described as a ratio of change in tangential angle in the direction of the force applied.

Volumetric strain - It is described as the volume change ratio to the original volume.