Data refers to information or facts usually collected as the result of experience, observation or experiment, or processes within a computer system, or premises. Data may consist of numbers, words, or images, particularly as measurements or observations of a set of variables. Data are often viewed as a lowest level of abstraction from which information and knowledge are derived.
Usage in English
Some British and UN academic, scientific and professional style guides request that authors treat data as a plural noun. Other international organizations, such as the Institute of Electrical and Electronics Engineers Computer Society, allow its usage as either a mass noun or plural based on author preference. The Air Force Flight Test Center, in its publication The Author's Guide to Writing Air Force Flight Test Center Technical Reports specifically states that the word data is always plural, never singular.
Data is now often treated as a singular mass noun in informal usage, but usage in scientific publications shows a divide between the United States and United Kingdom. In the United States the word data is sometimes used in the singular, though scientists and science writers more often maintain the traditional plural usage. Some major newspapers such as the New York Times use it alternately 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 on the same day. In scientific writing data is often treated as a plural, as in These data do not support the conclusions, but many people now think of data as a singular mass entity like information and use the singular in general usage." British usage now widely accepts treating data as singular in standard English, including everyday newspaper usage at least in non-scientific use. UK scientific publishing still prefers treating it as a plural. Some UK university style guides recommend using data for both singular and plural use and some recommend treating it only as a singular in connection with computers.
