of differences in technology, terminology and language, customs and attitudes, or even fashions between different historical periods and eras.

Types

The metachronism-prochronism contrast is nearly synonymous with parachronism-anachronism, and involves postdating-predating respectively.

Parachronism

A parachronism (from the Greek ????, "on the side", and ??????, "time") postdates or predates. It is anything that appears