The bowline ( or ) is an ancient and simple knot used to form a fixed loop at the end of a rope. It has the virtues of being both easy to tie and untie; most notably, it is easy to untie after being subjected to a load. The bowline is sometimes referred to as King of the knots because of its importance. Along with the sheet bend and the clove hitch, the bowline is often considered one of the most essential knots. The common bowline shares some structural similarity with the sheet bend. Virtually all end-to-end joining knots (i.e., bends) have a corresponding loop knot. Although the bowline is generally considered a reliable knot, its main deficiencies are a tendency to work loose when not under load (or under cyclic loading), to slip when pulled sideways, and the bight portion of the knot to capsize in certain circumstances. To address these shortcomings, a number of more secure variations of the bowline have been developed for use in safety-critical applications, or by securing the knot with an overhand knot backup. History The bowline's name has an earlier meaning, dating to the age of sail. On a square-rigged ship, a bowline (sometimes spelled as two words, bow line) is a rope that holds the edge of a square sail towards the bow of the ship and into the wind, preventing it from being taken aback. A ship is said to be on a "taut bowline" when these lines are made as taut as possible in order to sail close-hauled to the wind. The bowline knot is thought to have been first mentioned in John Smith's 1627 work A Sea Grammar under the name Boling knot. Smith considered the knot to be strong and secure, saying, "The Boling knot is also so firmly made and fastened by the bridles into the cringles of the sails, they will break, or the sail split before it will slip." Another possible finding was discovered on the rigging of the Ancient Egyptian Pharaoh Khufu's solar ship during an excavation in 1954. Usage The bowline is used to make a loop at one end of a line. It is tied with the rope's working end also known as the "tail" or "end". The loop may pass around or through an object during the making of the knot. The knot tightens when loaded at (pulled by) the standing