Reefing

Reefing may occur by rolling the sail around its luff or foot, either on a rotating stay or within a spar.

In a mainsail, reefing cringles may be installed in the sail; a cruising boat will typically have two to three pairs.

[2][1][3] Slab or jiffy reefing allows for the quick establishment of a new tack and clew, while the halyard is partially lowered and then raised.

[4][5] Roller reefing rolls or wraps the sail around a wire, foil, or spar to reduce its exposure to the wind.

Furling systems controlled with lines led to the cockpit allow reefing without crew having to go on deck in heavy weather.

Reefed Sail
Gaff sail, showing reefing cringles (13), reefing points (20) and reefing lines (21)
A genoa jib completely furled around the forestay, and mainsail partially furled within the mast (forming a reef) on a Bavaria 36 sloop
Square-rigged, 18th-century frigate , showing reef bands across the sails.