The traditional focuses of sociology include social stratification, social class, social mobility, religion, secularization, law, sexuality and deviance.
These were called calceus mulleus, and the name may have been shortened to mules by English speakers. Hence the primary difference between mules and clogs in early days was that clogs were likely to be worn by working people, and mules were fancier and favored by the aristocracy.
The hinny, or hinney, is also called a mule. However, the hinny is the hybrid cross between a male horse (stallion), and a female donkey (jenny, or jennet). The hinny is different from a mule in very subtle ways. For instance, the hinny is a somewhat slower and more meticulous mover than the mule.