Data (// DAY-tə, // DA-tə, or // DAH-tə) is a set of values of qualitative or quantitative variables. An example of qualitative data would be an anthropologist's handwritten notes about her interviews with people of an Indigenous tribe. Pieces of data are individual pieces of information. While the concept of data is commonly associated with scientific research, data is collected by a huge range of organizations and institutions, ranging from businesses (e.g., sales data, revenue, profits, stock price), governments (e.g., crime rates, unemployment rates, literacy rates) and non-governmental organizations (e.g., censuses of the number of homeless people by non-profit organizations).
Data is measured, collected and reported, and analyzed, whereupon it can be visualized using graphs, images or other analysis tools. Data as a general concept refers to the fact that some existing information or knowledge is represented or coded in some form suitable for better usage or processing. Raw data ("unprocessed data") is a collection of numbers or characters before it has been "cleaned" and corrected by researchers. Raw data needs to be corrected to remove outliers or obvious instrument or data entry errors (e.g., a thermometer reading from an outdoor Arctic location recording a tropical temperature). Data processing commonly occurs by stages, and the "processed data" from one stage may be considered the "raw data" of the next stage. Field data is raw data that is collected in an uncontrolled "in situ" environment. Experimental data is data that is generated within the context of a scientific investigation by observation and recording.
Etymology and terminology
The first English use of the word "data" is from the 1640s. "Data" is the "...plural of datum, from Latin datum "(thing) given," neuter past participle of dare "to give".  Using the word "data" to mean "transmittable and storable computer information" was first done in 1946.  The expression "data processing" was first used in 1954. Since the Latin word "data" is the plural of "datum", and still may be used as a plural noun in this sense, some writers in the 2010s use "data" in the singular and "datum" for plural. In the 2010s, though, in non-specialist, everyday writing, "data" is most commonly used in the singular, as a mass noun (like "information", "sand" or "rain").
Data, information, knowledge and wisdom are closely related concepts, but each has its own role in relation to the other, and each term has its own meaning. Data is collected and analyzed; data only becomes information suitable for making decisions once it has been analyzed in some fashion.  Knowledge is derived from extensive amounts of experience dealing with information on a subject. For example, the height of Mt. Everest is generally considered data. The height can be recorded precisely with an altimeter and entered into a database. This data may be included in a book along with other data on Mt. Everest to describe the mountain in a manner useful for those who wish to make a decision about the best method to climb it. Using an understanding based on experience climbing mountains to advise persons on the way to reach Mt. Everest's peak may be seen as "knowledge". Some complement the series "data", "information" and "knowledge" with "wisdom", which would mean the status of a person in possession of a certain "knowledge" who also knows under which circumstances is good to use it.
That is to say, data is the least abstract, information the next least, and knowledge the most abstract. Data becomes information by interpretation; e.g., the height of Mt. Everest is generally considered "data", a book on Mt. Everest geological characteristics may be considered "information", and a climber's guidebook containing practical information on the best way to reach Mt. Everest's peak may be considered "knowledge". "Information" bears a diversity of meanings that ranges from everyday usage to technical use. Generally speaking, the concept of information is closely related to notions of constraint, communication, control, data, form, instruction, knowledge, meaning, mental stimulus, pattern, perception, and representation. Beynon-Davies uses the concept of a sign to differentiate between data and information; data is a series of symbols, while information occurs when the symbols are used to refer to something.
Before the development of computing devices and machines, only people could collect data and impose patterns on it. Since the development of computing devices and machines, these devices can also collect data. In the 2010s, computers are widely used in many fields to collect data and sort or process it, in disciplines ranging from marketing, analysis of social services usage by citizens to scientific research. These patterns in data are seen as information which can be used to enhance knowledge. These patterns may be interpreted as "truth" (though "truth" can be a subjective concept), and may be authorized as aesthetic and ethical criteria in some disciplines or cultures. Events that leave behind perceivable physical or virtual remains can be traced back through data. Marks are no longer considered data once the link between the mark and observation is broken.
Mechanical computing devices are classified according to the means by which they represent data. An analog computer represents a datum as a voltage, distance, position, or other physical quantity. A digital computer represents a piece of data as a sequence of symbols drawn from a fixed alphabet. The most common digital computers use a binary alphabet, that is, an alphabet of two characters, typically denoted "0" and "1". More familiar representations, such as numbers or letters, are then constructed from the binary alphabet. Some special forms of data are distinguished. A computer program is a collection of data, which can be interpreted as instructions. Most computer languages make a distinction between programs and the other data on which programs operate, but in some languages, notably Lisp and similar languages, programs are essentially indistinguishable from other data. It is also useful to distinguish metadata, that is, a description of other data. A similar yet earlier term for metadata is "ancillary data." The prototypical example of metadata is the library catalog, which is a description of the contents of books.
In other fields
Though data is also increasingly used in other fields, it has been suggested that the highly interpretive nature of them might be at odds with the ethos of data as "given". Peter Checkland introduced the term capta (from the Latin capered, “to take”) to distinguish between an immense number of possible data and a sub-set of them, to which attention is oriented. Johanna Drucker has argued that since the humanities affirm knowledge production as "situated, partial, and constitutive," using data may introduce assumptions that are counterproductive, for example that phenomena are discrete or are observer-independent. The term capta, which emphasizes the act of observation as constitutive, is offered as an alternative to data for visual representations in the humanities.
- Biological data
- Data acquisition
- Data analysis
- Data cable
- Data domain
- Data element
- Data farming
- Data governance
- Data integrity
- Data maintenance
- Data management
- Data mining
- Data modeling
- Data visualization
- Computer data processing
- Data publication
- Data remanence
- Data set
- Data warehouse
- Environmental data rescue
- Open data
- Scientific data archiving
- Computer memory
- Data structure
- Raw Data
- Secondary Data
- The pronunciation // DAY-tə is widespread throughout most varieties of English. The pronunciation// DA-tə is chiefly Irish and North American. The pronunciation // DAH-tə is chiefly Australian, New Zealand and South African. Each pronunciation may be realized differently depending on the dialect/language of the speaker.
- Hickey, Walt (2014-06-17). "Elitist, Superfluous, Or Popular? We Polled Americans on the Oxford Comma". FiveThirtyEight. Retrieved 2015-05-04.
- "Joint Publication 2-0, Joint Intelligence" (PDF). Defense Technical Information Center (DTIC). Department of Defense. 22 June 2007. pp. GL–11. Retrieved February 22, 2013.
- Akash Mitra (2011). "Classifying data for successful modeling".
- P. Beynon-Davies (2002). Information Systems: An introduction to informatics in organisations. Basingstoke, UK: Palgrave Macmillan. ISBN 0-333-96390-3.
- P. Beynon-Davies (2009). Business information systems. Basingstoke, UK: Palgrave. ISBN 978-0-230-20368-6.
- Sharon Daniel. The Database: An Aesthetics of Dignity.
- P. Checkland and S. Holwell (1998). Information, Systems, and Information Systems: Making Sense of the Field. Chichester, West Sussex: John Wiley & Sons. pp. 86–89. ISBN 0-471-95820-4.
- Johanna Drucker (2011). "Humanities Approaches to Graphical Display".
|Look up data in Wiktionary, the free dictionary.|
- Data is a singular noun (a detailed assessment)