If an inclined plane is wrapped around a cylinder, the edge of the plane forms a shape called a helix.
Rotation of the cylinder causes a point on the helix to move, along the surface of the cylinder. The distance the point moves in one revolution of the cylinder is called the pitch.
The helix shape is commonly used as a thread on nuts and bolts, and also for teeth in steering gears, and transmissions.
Source: CDX Global
