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Data ( , , or ;〔The pronunciation is widespread throughout most Englishes. The pronunciation is chiefly Irish and North American. The pronunciation is chiefly New Zealand and Australian. Each pronunciation may be realized differently depending on the dialect of the speaker.〕 treated as singular, plural, or as a mass noun) is any sequence of one (1) or more symbols given meaning by specific act(s) of interpretation. Data is not information. Data requires interpretation to become information. To translate data to information, there must be several known factors considered. The factors involved are determined by the creator of the data and the desired information. The term metadata is used to reference the data about the data. Metadata may be implied, specified or given. Data relating to physical events or processes will also have a temporal component. In almost all cases this temporal component is implied. This is the case when a device such as a temperature logger received data from a temperature sensor. When the temperature is received it is assumed that the data has a temporal references of "now". So the device records the date, time and temperature together. When the data logger communicates temperatures, it must also report the date and time (metadata) for each temperature. Digital data is data that is represented using the binary number system of ones (1) and zeros (0). As opposed to analog representation. In modern (post 1960) computer systems, all data is digital. Data within a computer, in most cases, moves as parallel data. Data moving to or from a computer, in most cases, moves as serial data. See Parallel communication and Serial communication. Data sourced from an analog device, such as a temperature sensor, must pass through an "analog to digital converter" or "ADC" (see Analog-to-digital converter) to convert the analog data to digital data. Data representing quantities, characters, or symbols on which operations are performed by a computer, stored and recorded on magnetic, optical, or mechanical recording media, and transmitted in the form of digital electrical signals.〔(【引用サイトリンク】title=data )〕 A program is a set of data that consists of a series of coded software instructions to control the operation of a computer or other machine.〔(【引用サイトリンク】title=computer program )〕 Physical computer memory elements consist of an address and a byte/word of data storage. Digital data are often stored in relational databases, like tables or SQL databases, and can generally be represented as abstract key/value pairs. Data can be organized in many different types of data structures, including arrays, graphs, and objects. Data structures can store data of many different types, including numbers, strings and even other data structures. Data pass in and out of computers via 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). == Characteristics == At its most essential, a single datum is a value stored at a specific location. Fundamentally, computers follow a sequence of instructions they are given in the form of data. 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, are also data. The Marvellous twist is that program instructions; and data that the program manipulates, are both stored in exactly the same way. Therefore, it is possible for computer programs to operate on other computer programs, by manipulating their programmatic data. The line between program and data can become blurry. An interpreter, for example, is a program. The input data to an interpreter is itself a program, just not one expressed in native machine language. In many cases, the interpreted program will be a human-readable text file, which is manipulated with a text editor program (more normally associated with plain text data). Metaprogramming similarly involves programs manipulating other programs as data. Programs like compilers, linkers, debuggers, program updaters, virus scanners and such use other programs as their data. To store data bytes in a file, they have to be serialized in a "file format". Typically, programs are stored in special file types, different from those used for other data. Executable files contain programs; all other files are also data files. However, executable files may also contain "in-line" data which is "built-in" to the program. In particular, some executable files have a data segment, which nominally contains constants and initial values (both data). For example: a user might first instruct the operating system to load a word processor program from one file, and then edit a document stored in another file with the word processor program. In this example, the document would be considered data. If the word processor also features a spell checker, then the dictionary (word list) for the spell checker would also be considered data. The algorithms used by the spell checker to suggest corrections would be either machine code data or text in some interpretable programming language. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Data (computing)」の詳細全文を読む スポンサード リンク
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