- published: 16 Jun 2012
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In computer science, data ( /ˈdeɪtə/ DAY-tə or /ˈdætə/) is information in a form suitable for use with a computer. Data is often distinguished from programs. A program is a sequence of instructions that detail a task for the computer to perform. In this sense, data is thus everything in a software that is not program code. Physical computer memory elements consist of an address and a byte/word of data storage. Digital data can be reduced to key/value pair combinations[citation needed]. Supersets[clarification needed] of this idea, where keys are derived, and values are arranged, relatively, are called data structures. They are also used in peripheral devices.
In an alternate usage, binary files (which are not human-readable) are sometimes called "data" as distinguished from human-readable "text". The total amount of digital data in 2007 was estimated to be 281 billion gigabytes (= 281 exabytes).
Fundamentally, computers follow the instructions they are given. A set of instructions to perform a given task (or tasks) is called a "program". In the nominal case, the program, as executed by the computer, will consist of binary machine code. The elements of storage manipulated by the program, but not actually executed by the CPU, contain data.
Data ( /ˈdeɪtə/ DAY-tə, /ˈdætə/ DA-tə, or /ˈdɑːtə/ DAH-tə) are values of qualitative or quantitative variables, belonging to a set of items. Data in computing (or data processing) are often represented by a combination of items organized in rows and multiple variables organized in columns. Data are typically the results of measurements and can be visualised using graphs or images. Data as an abstract concept can be viewed as the lowest level of abstraction from which information and then knowledge are derived. Raw data, i.e., unprocessed data, refers to a collection of numbers, characters and is a relative term; data processing commonly occurs by stages, and the "processed data" from one stage may be considered the "raw data" of the next. Field data refers to raw data collected in an uncontrolled in situ environment. Experimental data refers to data generated within the context of a scientific investigation by observation and recording.
The word data is the plural of datum, neuter past participle of the Latin dare, "to give", hence "something given". In discussions of problems in geometry, mathematics, engineering, and so on, the terms givens and data are used interchangeably. Such usage is the origin of data as a concept in computer science or data processing: data are numbers, words, images, etc., accepted as they stand.