What is the displacement?

Displacement is the smallest distance between two points.

For example, let us assume that a person traveled from A to C through B. The distance he traveled to reach point B from A is 3 units and the distance he traveled to reach C from B is 4 units.

Here the distance traveled by him from A to C is 3 + 4 = 7 units.

But since the displacement is the smallest distance between two points, the displacement traveled by him is 5 units.