The reins run from the handler's hands to the horse's headstall, normally connecting to the bit. They are a vital line of communication between the horse and handler.
Riding reins are the most common type and are normally what is meant by "reins" if it is not pre-fix by another word. Traditionally reins are made of leather of the same colour as the bridle. Reins can also be made from cotton, nylon, cotton rope or a synthetic leather-look material, these will be cheaper, though not as smart or as durable as well-maintained leather. It is common to have reins of the same colour and material as the bridle. Synthetic reins can be a danger as they are much stronger then leather and will not brake if the horse becomes entangles in them. A weak link should always be placed at the buckle of synthetic reins to prevent this.
Plain leather reins are common for dressage and showing as they are the smartest, but most people prefer reins with some form of grip. The most common is the rubber covered reins with give excellent grip but can be bulky. Half-rubber reins only have rubber on the inside and therefore are less bulky and have a smarter appearance. More traditionally reins are laced or plaited to give extra grip.
Some reins have two stiff strip attached at each end called martingale stops. These are to prevent a martingale becoming tangled in the bit. Rubber martingale stops can be bought sepratelly.
There are many different types of attachment to attach the reins ot the bit (or bridle). The most common type for leather reins is the billet, but buckles are becomes more common. For showing reins are sometimes sewn on to the bit. This is the neatest way but makes changing the bit difficult.
A rider's favourite reins is very individual. When choosing reins gloves must also be considered. Gloves can grip extra grip, protect the riders hands and effect the feel of the reins.
Driving reins are used when driving a horse in harness or when long reining them. The use of nylon and cotton is more common on driving reins become of it's lightness. As the reins must be attached and removed from the bridle with ever use buckles are more common on driving reins as they are easier to use.
Lunge reins are single reins about 9m in length. They are used for lunging, usually attached to a lunge cavesson, but a more experienced handler and horse can attach them to the bit. Two lunge reins can be used to long rein a horse. They can be made from nylon, cotton or rope. They should always have a swivel just below the attachment, which is most commonly a clip, but some have a buckle.