In programming languages a data type is an attribute of a datum which tells the computer (and the programmer) something about the kind of datum it is. A programming language is an Artificial language that can be used to write programs which control the behavior of a machine particularly a Computer. Debt AIDS Trade in Africa (or DATA) is a Multinational non-government organization founded in January 2002 in London by U2 's This involves setting constraints on the datum, such as what values it can take and what operations may be performed upon it. Common data types may include: integers, floating-point numbers (decimals), and alphanumeric strings. In computer science the term integer is used to refer to a Data type which represents some finite subset of the mathematical Integers These are also known as In Computing, floating point describes a system for numerical representation in which a string of digits (or Bits represents a Real number. In Computer programming and some branches of Mathematics, a string is an ordered Sequence of Symbols. For example, in the Java programming language, the "int" type represents the set of 32-bit integers ranging in value from -2,147,483,648 to 2,147,483,647, as well as the operations that can be performed on integers, such as addition, subtraction, and multiplication. The range of Integer values that can be stored in 32 bits is 0 through 4294967295 or −2147483648 through 2147483647 using Two's complement encoding In computer science the term integer is used to refer to a Data type which represents some finite subset of the mathematical Integers These are also known as Colors, on the other hand, are represented by three bytes denoting the amounts each of red, green, and blue, and one string representing that color's name; allowable operations include addition and subtraction, but not multiplication. A byte (pronounced "bite" baɪt is the basic unit of measurement of information storage in Computer science.
In a broad sense, a data type defines a set of values, and the allowable operations on those values[1]. Almost all programming languages explicitly include the notion of data type, though different languages may use different terminology. Most programming languages also allow the programmer to define additional data types, usually by combining multiple elements of other types and defining the valid operations of the new data type. For example, a programmer might create a new data type named "Person" that specifies that data interpreted as Person would include a name and a date of birth.
A data type can also be thought of as a constraint placed upon the interpretation of data in a type system, describing representation, interpretation and structure of values or objects stored in computer memory. In Computer science, a type system defines how a Programming language classifies values and expressions into '''types''', how it can In Computer science, a value is a sequence of Bits that is interpreted according to some Data type. In its simplest embodiment an object is an allocated region of storage The type system uses data type information to check correctness of computer programs that access or manipulate the data. In theoretical Computer science, correctness of an Algorithm is asserted when it is said that the algorithm is correct with respect to a specification.
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Machine data types
All data in computers based on digital electronics is represented as bits (alternatives 0 and 1) on the lowest level. A bit is a binary digit, taking a value of either 0 or 1 Binary digits are a basic unit of Information storage and communication The smallest addressable unit of data is a group of bits called a byte (usually an octet, which is 8 bits). A byte (pronounced "bite" baɪt is the basic unit of measurement of information storage in Computer science. In Computing, an octet is a grouping of eight Bits Octet, with the only exception noted below always refers to an entity having exactly eight The unit processed by machine code instructions is called a word (as of 2006, typically 32 or 64 bits). Machine code or machine language is a system of instructions and data executed directly by a Computer 's Central processing unit. In Computing, " word " is a term for the natural unit of data used by a particular computer design Most instructions interpret the word as a binary number, such that a 32-bit word can represent unsigned integer values from 0 to 232 − 1 or signed integer values from − 231 to 231 − 1. The binary numeral system, or base-2 number system, is a Numeral system that represents numeric values using two symbols usually 0 and 1. Because of two's complement, the machine language and machine don't need to distinguish between these unsigned and signed data types for the most part. The two's complement of a Binary number is defined as the value obtained by subtracting the number from a large power of two (specifically from 2 N for
There is a specific set of arithmetic instructions that use a different interpretation of the bits in word as a floating-point number. In Computing, floating point describes a system for numerical representation in which a string of digits (or Bits represents a Real number.
Primitive types
Composite types
- Further information: Tuple
- Further information: Array
- Further information: Storage record
- Further information: Object composition
Abstract data types
Pointer and reference types
- Further information: Pointer
Algebraic types
Object types
- Further information: Class (computer science)
Function types
See also
- Data dictionary
- Type theory for the mathematical models of types
- Type system for different choices in programming language typing
Notes
References
- Luca Cardelli, Peter Wegner. In Computer science, primitive types — as distinct from Composite types ' — are Data types provided by a Programming language as basic In Computer science, composite types are Datatypes which can be constructed in a Programming language out of that language's Primitive types and In Mathematics, a tuple is a Sequence (also known as an "ordered list" of values called the components of the tuple In Computer science an array is a Data structure consisting of a group of elements that are accessed by indexing. In Computer science, a storage record is A group of related data words or fields treated as a meaningful unit for instance a Name Address and Telephone Number In Computer science, object composition (not to be confused with function composition) is a way and practice to combine simple objects or In Computing, an abstract data type ( ADT) is a specification of a set of data and the set of operations that can be performed on the data In Computer science, a reference is an object containing information which refers to data stored elsewhere as opposed to containing the data itself In Computer programming, an algebraic data type is a Datatype each of whose values is data from other datatypes wrapped in one of the constructors of the In its simplest embodiment an object is an allocated region of storage In Object-oriented programming, a class is a Programming language construct that is used as a blueprint to create objects This blueprint includes attributes Type signature is a term that is used in computer programming A data dictionary, as defined in the IBM Dictionary of Computing is a "centralized repository of information about data such as meaning relationships to other data origin In Mathematics, Logic and Computer science, type theory is any of several Formal systems that can serve as alternatives to Naive set theory In Computer science, a type system defines how a Programming language classifies values and expressions into '''types''', how it can On Understanding Types, Data Abstraction, and Polymorphism, [1] from Computing Surveys, (December, 1985)
Dictionary
data type
-noun
- (computing) a classification or category of various types of data, that states the possible values that can be taken, how they are stored, and what range of operations are allowed on them
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