Mule

The term mule (Latin mulus) formerly applied to the offspring of any two creatures of different species -- in modern usage, a "hybrid". In its common modern meaning, "mule" describes the offspring of a male donkey and a female horse. Compare hinny -- the offspring of a male horse and a female donkey.

The mule, easier to breed and usually larger in size than a hinny, has monopolised the attention of breeders. Male mules and hinnies are both sterile, as are most female mules and hinnies.

Characteristics

In its short thick head, long ears, thin limbs, small narrow hooves, short mane, absence of chestnuts (horny growths) inside the hocks, and tail destitute of hair at the root, the mule appears asinine in form. In height and body, shape of neck and croup, uniformity of coat, and teeth, it appears equine. It has the voice neither of the ass nor of the horse, but emits a feeble hoarse noise. Most mules have a brown or bay-brown coat -- bay, or bright bay, or piebald occur rarely; a chestnut tint sometimes appears.

The mule possesses the sobriety, patience, endurance and sure-footedness of the ass, and the vigour, strength and courage of the horse. Operators of Mysia and Paphlagonia allegedly bred the first ones. The ancient Greeks and especially Romans valued mules for transport, employing them to draw carriages and carry loads. Mules hauled barges in the early days of the Erie Canal. In the early 20th century use of mules survived mainly in military transport, being used to haul caissons and artillery through nearly impassable terrain, the bravery and focused intelligence of the animal serving it well in the midst of the noise and confusion of warfare.

Mules have become far less common since the rise of the automobile, the motorized tractor, and other internal combustion-powered vehicles. They still find employment in less-developed countries, and in certain specialized roles for which they are still aptly suited. Mules can negotiate well on narrow, steep trails -- such as the route from the South Rim down into the Grand Canyon. (The animal used for tourist transport on the Bright Angel Trail in the Grand Canyon is the mule's smaller but even more sure-footed 'cousin', the burro.) Mules (and burros) can handle extremely rugged terrain and tracks that are too steep and twisted for either the less sure-footed horse or for a motor vehicle.

based on an article from 1911 Encyclopedia Britannica

Muleshoe, Texas has a The Mule appears as a fictional character in Isaac Asimov's Foundation Series.

Smuggling

Modern usage may designate as a mule someone who, knowingly or unknowingly smuggles something onto an airplane or across a national border, sometimes aware that they are in fact smuggling, but being unaware of the actual contents of what he or she smuggles. For example, a terrorist may tell someone that a package contains diamonds and persuade him or her to smuggle it; however, the package actually contains a bomb. Anyone transporting drugs might be referred to as a drug mule.

'Mules" in gaming

In video games, and in particular in Massively Multiplayer On-line Roleplaying Games a mule is a subsidiary character used as a beast of burden. Rather than using this character to actively participate in the game, the player who controls it just needs a way to hold and transport goods, and perhaps to obtain more of some resources which are limited on a per-character basis by the game rules.

Many people regard the need for or use of mules in a game as a design flaw. In the game Diablo 2 'mules' are sometimes used to 'smuggle' items from Diablo 2 Classic to Diablo 2, Lord of Destruction the game's expansion -- some items do not exist in both games. This type of smuggling is a one-way venture, as characters cannot make the return trip from Lord of Destruction to the 'classic version'. The use of mules in this manner circumvents the designed-in inability of characters to move freely from one version to the other, and some players consider this a 'cheat'.