Diglossia refers to a situation where two varieties of the same language are used by a single language community. One variety, labeled "H" or "high", is a highly codified lect used for formal settings like literature and education. The other variety, labeled "L" or "low", is the everyday vernacular language used for ordinary conversation. The term was first introduced and defined by linguist Charles A. Ferguson in 1959 to describe this pattern where two distinct forms of the same language are used within a speech community.