This document discusses various aspects of language variation based on region and geography. It defines key terms like standard language, accent, dialect, dialectology, regional dialects, isoglosses, dialect boundaries, dialect continuum, bilingualism, diglossia, pidgins, creoles, creolization, and language planning. Standard language refers to an idealized variety used in administration, education, and media regardless of region. Dialects vary based on pronunciation, vocabulary, and grammar depending on the geographic region.