Cleat
A cleat is a fitting on a boat that is used for attaching a line. There are several different types with different uses. Most cleats are designed to be used with a specific size of line and may not work well with the wrong size.
A horn cleat (or mooring cleat) has two horns. A line is cleated by wrapping the line around the cleat once, then crossing over the center diagonally, then secured by by putting a loop in the line that places the bitter end of the line under the standing end. The initial contact with the cleat should be at an acute angle.
A cam cleat uses two spring-loaded cams to grip the line. A line can usually be secured to a cam cleat by simply pulling it through the two cams. The line is released by pulling it up out of the cams.
A jam cleat has no moving parts but works by jamming the line in place by virtue of its shape. It incorporates a wedge shape to allow a line to be pulled easily in one direction, but it will grab hold of the line if it's pulled in the other direction. Much like a cam cleat, the line is release by pulling it up out of the cleat.
