Question

What is frame of reference or reference point.

Answer 1

All types of motion are observed with respect to some point because motion is always relative. Mostly, motion is taken relative to the earth. So the point to which the motion is taken relative to is the point of reference and if you take that as the origin and construct the Co ordinate axes it is a frame of reference. For example: There is a person in a car which is moving and another person on the road, taking the person in car as the frame of reference, the car is in rest, taking the person on the road as the frame of reference, the car is moving.

Answer 2

Reference body is the object with respect to which the state of rest or motionof an object is described