Block and tackle systems. A block is a set of pulleys or sheaves mounted on a single frame. An assembly of blocks with a rope threaded through the pulleys is called tackle. A block and tackle system amplifies the tension force in the rope to lift heavy loads. They are common on boats and sailing ships, where tasks are often performed manually. In the diagram shown here, the number of rope sections of the tackles shown is as follows: Note that the gun tackle, double tackle and threefold purchase all have the same number of pulleys in both blocks (one, two and three,
Rope control lines are mainly referred to as sheets (e.g. jibsheet). A halyard, for example, is a line used to raise and lower a sail, and is typically made of a length of rope with a shackle attached at one end. Other examples include clothesline, chalk line, anchor line ("rode"), stern line, fishing line, marline and so on. Rope A rope is a group of yarns, plies, fibers or strands that are twisted or braided together into a larger and stronger form. Ropes have tensile strength and so can be used for dragging and lifting. Rope is thicker and stronger than