Translation motion-
If a body is moving such that a line drawn between any two of its internal points remains parallel to itself.
All the particles of the body move along parallel paths.
All the particles of the body follow 1 D motion.
Example- Motion of a body along a straight line.
Rotational motion-
A rigid body is said to be in the pure rotation if every particle of the body moves in a circle and the center of all the circles lie on a straight line called the axis of rotation.
The line joining any two internal points does not remain parallel.
Example-motion of wheels, gears, motors.