The direction of frictional force in circular turning Why does the frictional force in case of circular motion point towards the center even though the motion is tangential to the radius?

 A: The force of friction acts both towards the centre of the circle and opposite the velocity vector of the car.
Strictly speaking, the diagram you have does not show all forces acting on the car but it is enough for purposes of explaining the circular motion.
As the text also explains, circular motion always requires a force pointed radially inwards because the object is changing its velocity. Newton's first law of motion tells us that a change in motion requires a force to act on the object.
A car driving through a curve "wants" to go in a straight path because of its inertia but it actually takes a turn. Because the force that provides the centripetal acceleration opposes the natural tendency of the car to move outwards, it is feasible for this force to be frictional in nature.
A: Imagine that friction between wheels and road disappeared in one second. Then the car would just go away moving straight along tangential direction, right? In the life it doesn't, consequently there is centripetal acceleration that keeps the car on the circle way. Consequently there is some force doing that. It is friction.
