Sail plans for various rigs The Sloop The most popular plan is the SLOOP, which has one mast forward of amidships and two sails. The forward sail is the HEADSAIL or JIB, and the aft one is the MAIN-SAIL, also called the MAIN. A sail's leading-edge is its LUFF; it's after edge is the LEECH and its bottom edge is the FOOT. The jib is attached to the HEADSTAY with HANKS, strong hooks with spring-loaded closures. An alternative design uses a semiflexible track, or FOIL, on the stay that accepts a BOLTROPE sewn along the sail's luff. Such tracks offer better air-flow over the luff, making the sail more efficient; this also allows ROLLER FURLING to reduce sail area in heavy weather. Some mainsails may be roller-furled into a slot in the mast or boom, making them easier to REEF. Headsails can have many names, depending on their size, weight, and shape. A STORM JIB is a small sail made of heavy cloth to be flown in heavy weather; a WORKINGJIB is flown in a moderate to fre...