The better-known forms of motion include rotary motion (turning round in a circle), linear motion (moving in a straight line), reciprocating motion (moving backward and forward in a straight line), oscillating motion (swinging from side to side), irregular motion (moving with no obvious pattern) and uniform motion (moving at constant speed in a straight line). Kinematics is the science that studies the motion of objects.
Motion is movement, and it can also be defined as a continuous change in the position of an object along a specific vector. Each type of motion is controlled by a different type of force.
There are two types of basic motion. Translation means motion along a path and is defined by the net force (the sum of different forces) acting on an object, while rotation means motion around a fixed axis and is defined by torque (force that causes the rotation of an object).
Many mechanisms take one type of input motion and output it as a different type of motion. For example, a chain and sprocket changes rotary motion to linear motion. A cam and follower changes rotary motion to reciprocating motion, and a peg and slot changes oscillating motion to rotary motion.