The magnitude of displacement is

(i)is less than distance when motion of the particle is not straight line $\left(\left|\overrightarrow{S}\right|<\text{S}\right)$ .

(ii) equal to zero, when the body returns to the initial point.

(iii) equal to distance when motion of the particle is straight line $\left(\left|\overrightarrow{S}\right|=\text{S}\right)$