Data (word)

The word data has generated considerable controversy on if it is a singular, uncountable noun, or should be treated as the plural of the now-rarely-used datum.

In one sense, data is the plural form of datum. Datum actually can also be a count noun with the plural datums (see usage in datum article) that can be used with cardinal numbers (e.g. "80 datums"); data (originally a Latin plural) is not used like a normal count noun with cardinal numbers and can be plural with such plural determiners as these and many or as an uncountable noun with a verb in the singular form. Even when a very small quantity of data is referenced (one number, for example) the phrase piece of data is often used, as opposed to datum. The debate over appropriate usage continues, but "data" as a singular form is far more common.

In English, the word datum is still used in the general sense of "an item given". In cartography, geography, nuclear magnetic resonance and technical drawing it is often used to refer to a single specific reference datum from which distances to all other data are measured. Any measurement or result is a datum, though data point is now far more common.

Data is most often used as a singular mass noun in everyday usage. Some major newspapers such as The New York Times use it either in the singular or plural. In the New York Times the phrases "the survey data are still being analyzed" and "the first year for which data is available" have appeared within one day. The Wall Street Journal explicitly allows this usage in its style guide. The Associated Press style guide classifies data as a collective noun that takes the singular when treated as a unit but the plural when referring to individual items ("The data is sound.", and "The data have been carefully collected.").

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