A term covering all the rope, chain, metalwork, and associated fittings used to support and operate the masts, spars, flags, sails, booms, and derricks of sailing vessels, and the masts, booms, and derricks of power vessels. The rigging used principally to support the masts and spars and which is fixed in nature is known as the standing rigging. That used to operate the sails and other equipment, which is adjustable, is known as running rigging.
Used where a mast is supported athwartships by shrouds and fore and aft by forestays and backstays. Historically, these were made of rope, sometimes specially built four-strand hawser-laid rope which had less stretch than three strand. This has been generally superseded by steel wire and, occasionally, solid stainless steel bar is used for performance sailing yachts where the smaller section can reduce wind drag. In early and small square-rigged ships the rope shrouds were set up by tackles which could be slacked or detached to allow the yard to swing closer to the centreline. Later and bigger vessels used deadeyes and lanyards, and these could also be slacked away to allow the yards to be swung closer.
Wire rope was originally used with deadeyes but these were superseded by bottlescrews. These are more efficient at stretching the longer and stronger wires, and can be retightened as required to counteract the stretching of the wire, but are not slacked away for any aspect of sailing. Stays followed a similar evolution except that they generally used hearts instead of deadeyes. Forestays and the backstays of square-riggers were not commonly slacked away, but the running backstays of fore-and-aft-rigged vessels have to be eased to allow the boom to swing clear over the ship's side when running before the wind. The running backstays of yachts are often operated by a lever system such as the Highfield lever.
The degree of use of standing rigging varies heavily with the type and rig of the vessel. The junk rig may not use any, and relies solely on the strength of its pole masts to support its sail; and vessels such as dhows use the falls of halyards and parrel tackles (both classed as running rigging) for mast support. Power vessels usually rely on a minimum of standing rigging to support masts which may carry only steaming lights, flags, aerials, and radar. Fore-and-aft-rigged sailing yachts support their masts with only the most basic standing rigging, often as little as a single forestay and a single backstay together with twin lower shrouds, and a single upper shroud, each side.
Big square-riggers have a more extensive system of standing rigging due to their size, the complexity of their masting, and the specific need to swing their yards around the masts. Each stack of sails of a classic square-rigged ship was likely to have three or even four component masts. To the one stepped into the hull would be added a topsail mast and a topgallant mast, and sometimes a royal mast. To these a clipper might add a skysail mast.