Language groups

A language family is a group of languages related through descent from a common ancestor, called the proto-language of that family. The term family is a metaphor borrowed from biology, with the tree model used in historical linguistics analogous to a family tree, or to phylogenetic trees of taxa used in evolutionary taxonomy. Linguists thus describe the daughter languages within a language family as being genetically related. The divergence of a proto-language into daughter languages typically occurs through geographical separation, with different regional dialects of the proto-language undergoing different language changes and thus becoming distinct languages over time.