Foresail

A foresail is a sail located forward of the mast. The luff of the sail is attached to the forestay, and the clew is usually attached to two sheets which are lead to either side of the boat.

Foresails can come in different sizes. The size of a foresail is designated by how far aft toward the mast the clew of the sail reaches. A 70% sail would only reach 70% of the way from the forestay to the mast, and a 130% sail would reach 130% past the mast, overlapping the mainsail (the actual formula is a bit more complicated).

A foresail that is 100% or less is called a jib. A sail that is more than 100% is called a genoa. However, in common usage, any size foresail is often just called a jib. The term working jib is sometimes used to specifically refer to a jib sail that is smaller than 100%.

Foresails are often numbered in decreasing order of their size. The #1 sail would be the largest genoa, and a working jib might be #3 or #4.