The impossibility of stating precisely how many “languages” or “dialects” are spoken in the world is due to the ambiguities of meaning present in these terms, which is shown to stem from the original use of “dialect” to refer to the literary dialects of ancient Greece. In most usages the term “language” is superordinate to “dialect,” but the nature of this relationship may be either linguistic or social, the latter problem falling in the province of sociolinguistics. It is shown how the development of a vernacular, popularly called a dialect, into a language is intimately related to the development of writing and the growth of nationalism. This process is shown to involve the selection, codification, acceptance, and elaboration of a linguistic norm.