Distance : The total length of the path covered by a body is known as distance . It is a scalar quantity .
Displacement : The distance covered by a body in a particular direction is known as displacement . It is a vector quantity .
Distance is the total path covered by a body from its origin. it can't be zero.
while Displacement is the shortest distance between initial point and final may be null.

if a runner runs with a circular field of radius r and completed one round after that he cover dist. = 2 \pi r and disp. = 0.

hope it helps..
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