Learn about etymology, the study of word origins and derivations in historical linguistics, and the influence of a Proto-Indoeuropean (PIE) language in the formation of modern languages in Europe, Russia, and Asia. Highlighted is how etymologists have come up with a theoretical model of the Proto-Indoeuropean language; how Modern English was influenced by the Proto-Germanic and Latin languages, both descendants of PIE; and how English continues to borrow words from other languages.