data

First recorded in 1640–50; from Latin, plural of datum

Data is a plural of datum, which is originally a Latin noun meaning “something given.” Today, data is used in English both as a plural noun meaning “facts or pieces of information” (These data are described more fully elsewhere) and as a singular mass noun meaning “information” (Not much data is available on flood control in Brazil) . It is almost always treated as a plural in scientific and academic writing. In the digital or computer sense it is usually treated as a mass noun and used with a singular verb. In other types of writing it is either singular or plural. The Latinate singular datum meaning “a piece of information” is now rare in all types of writing. In surveying and civil engineering, where datum has specialized senses, the plural form is datums.