Bit (horse)

A bit is a type of horse tack used in equestrian activities, usually made of metal or a synthetic material, and is placed in the mouth of a horse or other equid and assists a rider in communicating with the animal. It rests on the bars of the mouth in an interdental region where there are no teeth. It is held on a horse's head by means of a bridle and has reins attached for use by a rider.

Although there are hundreds of design variations, the basic families of bits are defined by the way in which they use or do not use leverage. They include:

Bits are further described by the style of mouthpiece that goes inside the horse's mouth as well as by the type of bit ring or bit shank that is outside the mouth, to which the reins are attached.

Types of headgear for horses that exert control with a noseband rather than a bit are usually called hackamores, though the term "bitless bridle" has become a popular colloquialism in recent years.

The riders of early domesticated horses probably used some type of bitless headgear made of sinew, leather, or rope. Components of the earliest headgear may be difficult to determine, as the materials would not have held up over time. For this reason, no one can say with certainty which came first, the bitted or the bitless bridle. There is evidence of the use of bits, located in two sites of the Botai in ancient Kazakhstan, dated about 3500-3000 BC.Nose rings appear on the equids portrayed on the Standard of Ur, circa 2600 BC - 2400 BC. To date, the earliest known artistic evidence of use of some form of bitless bridle comes in illustrations of Synian horseman, dated approximately 1400 BC.

The first bits were made of rope, bone, horn, or hard wood. Metal bits came into use between 1300 and 1200 BC, originally made of bronze. In modern times, nickel was a favored material until about 1940, when stainless steel largely replaced it.Copper, aurigan and sweet iron (cold rolled steel) are incorporated into some bits to encourage salivation in the mouth of the horse, which encourages a softer mouth and more relaxed jaw. Bits also can be made of other materials such as rubber or plastic, sometimes in combination with metals.

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