This animated site is a superb learning resource.
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The most useful Knots to know at sea.
· Round Turn & Two Half Hitches; This reliable knot is quickly tied and is the hitch most often used in mooring.
· Clove Hitch; This knot is the "general utility" hitch for when you need a quick, simple method of fastening a rope around a post, spar or stake.
· Bowline; This knot forms a loop which doesn't jam or slip when tied properly.
· Figure of Eight; This knot is ideal for keeping the end of a rope from running out of tackle or pulley.
· Reef or Square Knot; This knot is used at sea in reefing and furling sails.
· Sheet Bend; To tie two lines of dissimilar diameter
· Anchor Bend; This knot is used to secure a rope or a line to an anchor.
· Cleat Hitch; In order to secure the boat to a dock or secure a line to the boat you will probably use the cleat hitch.
· Rolling Hitch; This is like a clove hitch with another turn. Ideal for taking the strain off another rope.

