Motion : - A body is said to be in motion when its position changes continuously with respect to a stationary object taken as a reference point.

Locomotion : - The movement in animal is known as locomotion.

Distance : - The total distance covered by a body from the initial position to arrive at the final position is called distance.

Displacement : - The shortest distance measured from the initial to the final position of a body is known as the displacement.

Vectors : - Physical quantities which need to be specified by magnitude as well as direction are called vectors or vector quantities.

Scalars : - Quantities, which can be specified by magnitude, only are called scalars or scalar quantities.

Uniform motion : - If a body covers equal distance in equal intervals of times it is said to be in uniform motion.

Non-uniform motion : - A body is said to be in non-uniform motion if the distance moved by it in equal intervals of time is not the same.

Speed : - The distance moved by a body in unit time is called its speed.

Unifrorm Speed :- When a body covers equal displacement in equal intervals of time it is said to be uniform speed.

Non-Unifrorm Speed :- When a body covers unequal displacement in equal intervals of time it is said to be non-uniform speed.

Average Speed : - Total distance travelled by a body per unit time is known as average speed.

Velocity : - The distance moved by a body in a given direction in unit time is called its velocity.

Average Velocity : - The mean of initial velocity and final velocity is known as average velocity.

Acceleration : - The rate of change of velocity is known as acceleration.

Reatardation : - THe rate of decrease in velocity is known as Retardation.

Circular Motion : - When a body moves in a circular path With constant speed is known as CIrcular motion.