Data types

The bit is the most basic unit of information in computing and digital communication. The name is a portmanteau of binary digit. The bit represents a logical state with one of two possible values. These values are most commonly represented as , but other representations such as true/false, yes/no, on/off, and +/− are also widely used.

The byte is a unit of digital information that most commonly consists of eight bits. Historically, the byte was the number of bits used to encode a single character of text in a computer and for this reason it is the smallest addressable unit of memory in many computer architectures. To disambiguate arbitrarily sized bytes from the common 8-bit definition, network protocol documents such as the Internet Protocol () refer to an 8-bit byte as an octet.

classification of data in computer science

abstract data type

data type representing a finite sequence of encoded characters

programming element that groups data with relevant operations/behaviors

in programming languages and type theory, accessing different types using a common interface

storage location paired with a name, which contains a value

primitive data type

basic computing representation of truth and falsehood

datum of integral data type

base memory unit handled by a computer

set of rules that assign a property called type to various constructs a computer program consists of, such as variables, expressions, functions or modules

mathematical model for data types

data type that associates keys with values

abstract data type used in computer science

function definition that is not bound to an identifier

value that gives indirect access to e.g. a variable or register

composite data type; information block containing specific, identified fields

abstract data type in computer science

changing an expression from one data type to another

purely abstract class in object-oriented programming

computer format for representing real numbers

data type consisting of an unordered set of named values

abstract data type that simulates a pointer while providing added features, such as automatic memory management or bounds checking, intended to reduce bugs caused by the misuse of pointers, while retaining efficiency

C++ mechanism that exposes information about an object's data type at runtime

data collected from a source, has not been subject to any other manipulation by a software program or a human researcher, analyst or technician

multidimensional search tree for points in k dimensional space

in programming languages, a keyword indicating the absence of data

basic data type which can be instanciated and used with the predefined operations of a programming language, or assembled as a building block together with other instances of any type to create more complex composite data types

in computer programming, a type formed by combining other types

method for bounding the errors of numerical computations

programming language feature that allows manipulating functions like other values

abstract reference to an open or active computing resource

representation of memory address

data type supported by the C programming language

data structure

In programming language theory, subtyping (also called subtype polymorphism or inclusion polymorphism) is a form of type polymorphism. A subtype is a datatype that is related to another datatype (the supertype) by some notion of substitutability, meaning that program elements (typically subroutines or functions), written to operate on elements of the supertype, can also operate on elements of the subtype.

In computer programming, '''' ( or ) is a fundamental function in most dialects of the Lisp programming language. constructs memory objects which hold two values or pointers to two values. These objects are referred to as (cons) cells, conses, non-atomic s-expressions ("NATSes"), or (cons) pairs. In Lisp jargon, the expression "to cons x onto y" means to construct a new object with (cons x y). The resulting pair has a left half, referred to as the (the first element, or contents of the address part of register), and a right half, referred to as the (the second element, or contents of the decre

data type that refers to itself in its definition

type qualifier in C, C++, D, JavaScript, Julia and Rust

data structure used to hold a value that could take on several different, but fixed, types

collection of character data in a database management system

encapsulation of an optional value in programming or type theory

programming datatype

type system construct for ad-hoc polymorphism

data type that represents a collection of elements (values or variables)

type allowing only one value in type theory

one-dimensional (real) variable in a computing context

any data type which can be constructed in a program using the programming language's primitive data types and other composite types

A VARCHAR or variable character field is a set of character data of indeterminate length. The term varchar refers to a data type of a field (or column) in a database which can hold letters and numbers. Varchar fields can be of any size up to a limit, which varies by databases: an Oracle 11g database has a limit of 4000 bytes, a MySQL 5.7 database has a limit of 65,535 bytes (for the entire row) and Microsoft SQL Server 2008 has a limit of 8000 bytes (unless varchar(max) is used, which has a maximum storage capacity of 2 gigabytes).

type of types in a type system

In computing, signedness is a property of data types representing numbers in computer programs. A numeric variable is signed if it can represent both positive and negative numbers, and unsigned if it can only represent non-negative numbers (zero or positive numbers).

computer file which stores data to be used by a computer application or system

algebraic term to describe the result of multiplying data types in type theory

Concept in functional programming

type that is the subtype of all other types; equivalent to the empty type if uninhabited

type of data