A hitch is a knot tied in a line and used to secure that line to another object. The object may be a cleat, post, ring, hook or even another rope. That object contributes nothing mechanically to the fastening of the knot beyond its function as a point of attachment for the knot in the line.
The choice of hitch will be influenced by the shape of the object to which the line is to be attached. A Highwayman's hitch will attach well to a rail while a Ossel hitch is a good choice to bind to another rope.
