The donkey or ass is a domesticated animal of the horse family.
Donkeys have a reputation for stubbornness, but this is due to some handlers' misinterpretation of their highly developed sense of self preservation.
It is difficult to force or frighten a donkey into doing something it sees as contrary to its own best interest, as opposed to horses who are much more willing to, for example, go along a path with unsafe footing.
Although formal studies of their behaviour and cognition are rather limited, donkeys appear to be quite intelligent, cautious, friendly, playful, and eager to learn.
They are many times fielded with horses due to a perceived calming effect on nervous horses.