THE HORSE - EL CABALLO
Almost all breeds of horses can, at least in theory, carry humans on their backs or be harnessed to pull objects such as carts or plows. However, horse breeds were developed to allow horses to be specialized for certain task; lighter horses for racing or riding, heavier horses for farming and other tasks requiring pulling power. In some societies, horses are a source of food, both meat and milk; in others it is taboo to consume them. In industrialized countries horses are predominantly kept for leisure and sporting pursuits, while they are still used as working animals in many other parts of the world.
Size
The size of horses varies by breed, but can also be influenced by nutrition. The general rule for cutoff in height between what is considered a horse and a pony at maturity is 14.2 hands high. (abbreviated "h" or "hh") (147 cm, 58 inches) as measured at the withers. An animal 14.2h or over is usually considered a horse and one less than 14.2h is a pony.
However, there are exceptions to the general rule. Some smaller horse breeds who typically produce individual horses both under and over 14.2h are considered "horses" regardless of height. Likewise, some pony breeds, such as the Pony of the Americas or the Welsh pony, share some features of horses and individual animals may occasionally mature at over 14.2h, but are still considered ponies.
The difference between a horse and pony is not simply a height difference, but also a difference in phenotype or appearance. There are noticeable differences in conformation and temperament. Ponies often exhibit thicker manes, tails and overall coat. They also have proportionally shorter legs, wider barrels, heavier bone, shorter and thicker necks, and short heads with broad foreheads. They often have calmer temperaments than horses, but also a high level of equine intelligence that may or may not be used to cooperate with human handlers.
Light riding horses such as Arabians, Morgans, or Quarter Horses usually range in height from 14.0 (142 cm) to 16.0 hands (163 cm) and can weigh from 386 kilograms (850 lbs) to about 540 kg (1200 lbs). Larger riding horses such as Thoroughbreds, American Saddlebreds or Warmbloods usually start at about 15.2 hands (157 cm) and often are as tall as 17 hands (172 cm), weighing from 500 kg (1100 lbs) to 680 kg (1500 lbs). Heavy or draft horses such as the Clydesdale, Belgian, Percheron, and Shire are usually at least 16.0 (163 cm) to 18.0 hands (183 cm) high and can weigh from about 680 kg (1500 lb) up to about 900 kg (2000 lb). Ponies cannot be taller than 14.2h, but can be much smaller, down to the Shetland pony at around 10 hands, and the Falabella which can be the size of a medium-sized dog. However, while many miniature horse breeds are small as or smaller than a shetland pony, because they are bred to have a horse phenotype (appearance), their breeders and registries classify them as very small horses rather than ponies.
The largest horse in history was a Shire horse named Sampson, later renamed Mammoth, foaled in 1846 in Bedfordshire, England. He stood 21.2½ hands high (i.e. 7 ft 2½ in or 2.20 m ), and his peak weight was estimated at over 3,300 lb (approx 1.5 tonnes). The current record holder for the world's smallest horse is Thumbelina, a fully mature miniature horse affected by dwarfism. She is 17 inches tall and weighs 60 pounds.