Sailcloth
Sails have been made from cloth for all of recorded history. Typically sailcloth is' made from flax (linen), hemp or cotton in various forms including canvas. However, modern sails are rarely made from natural fibers. Most sails are made from synthetic fibers ranging from low-cost nylon or polyester to expensive aramids or carbon fibers. Recent strides in technology now offer many options for the sailmaker.
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