The four unchanging principals of animal draft are: steering, transmission, weight distribution and braking. Correspondingly, there are four component parts of harness designed to accommodate these. They are: the bridle, collar, pad and breeching. Independently, each of these component parts plays a vital role in harnessing the forces of draught.
Animal power world-wide
Domestic work animals exist in all regions of the world. Animals assist in eliminating
poverty, reducing drudgery and creation of wealth. Animal traction is particularly important for food security in smallholder farming systems. Animals can assist directly with crop production (ploughing, planting, and weeding). Food production, distribution and rural trade
are also assisted through animal-powered transport (on-farm, marketing, riding, pack transport). Animals save household (women and children) time and effort by carrying water and fuel wood. Animal power can also be used for water-lifting, milling, logging and land excavation and road construction. Many different types of animal are employed, particularly cattle (oxen, bulls and cows), buffaloes, horses, mules, donkeys and camels.