# Boolean data type

booleanBoolean variableBoolean valueBoolean typeBoolean datatypebooleansbooltrueboolean valuesBoolean variables
In computer science, the Boolean data type is a data type that has one of two possible values (usually denoted true and false) which is intended to represent the two truth values of logic and Boolean algebra.wikipedia
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### Data type

typedatatypetypes
In computer science, the Boolean data type is a data type that has one of two possible values (usually denoted true and false) which is intended to represent the two truth values of logic and Boolean algebra. This approach with boolean as a built-in (either primitive or otherwise predefined) data type was adopted by many later programming languages, such as Simula 67 (1967), ALGOL 68 (1970), Pascal (1970), Ada (1980), Java (1995), and C# (2000), among others.
Most programming languages support common data types of real, integer and boolean.

### Truth value

truth-valuelogical valuetruth values
In computer science, the Boolean data type is a data type that has one of two possible values (usually denoted true and false) which is intended to represent the two truth values of logic and Boolean algebra.
In some programming languages, any expression can be evaluated in a context that expects a Boolean data type.

### Conditional (computer programming)

conditionalif-then-elseconditional statement
The Boolean data type is primarily associated with conditional statements, which allow different actions by changing control flow depending on whether a programmer-specified Boolean condition evaluates to true or false. Conditional and iterative commands may be defined to test Boolean-valued expressions.
In computer science, conditional statements, conditional expressions and conditional constructs are features of a programming language, which perform different computations or actions depending on whether a programmer-specified boolean condition evaluates to true or false.

### Relational operator

comparisonComparecomparison operator
In programming languages with a built-in Boolean data type, such as Pascal and Java, the comparison operators such as and are usually defined to return a Boolean value.
In programming languages that include a distinct boolean data type in their type system, like Pascal, Ada, or Java, these operators usually evaluate to true or false, depending on if the conditional relationship between the two operands holds or not.

### While loop

while loop
Conditional and iterative commands may be defined to test Boolean-valued expressions.
In most computer programming languages, a while loop is a control flow statement that allows code to be executed repeatedly based on a given Boolean condition.

### George Boole

BooleBoole, GeorgeBoole, G
It is named after George Boole, who first defined an algebraic system of logic in the mid 19th century.
The keyword Bool represents a Boolean datatype in many programming languages, though Pascal and Java, among others, both use the full name Boolean.

### Control flow

looploopscontrol structure
The Boolean data type is primarily associated with conditional statements, which allow different actions by changing control flow depending on whether a programmer-specified Boolean condition evaluates to true or false.

### Java (programming language)

JavaJava programming languageJava language
In programming languages with a built-in Boolean data type, such as Pascal and Java, the comparison operators such as and are usually defined to return a Boolean value. This approach with boolean as a built-in (either primitive or otherwise predefined) data type was adopted by many later programming languages, such as Simula 67 (1967), ALGOL 68 (1970), Pascal (1970), Ada (1980), Java (1995), and C# (2000), among others.
All code is written inside classes, and every data item is an object, with the exception of the primitive data types, (i.e. integers, floating-point numbers, boolean values, and characters), which are not objects for performance reasons.

### Integer (computer science)

integerintegerslong integer
The C programming language uses an integer type, where relational expressions like and logical expressions connected by and are defined to have value 1 if true and 0 if false, whereas the test parts of,,, etc., treat any non-zero value as true.
A Boolean or Flag type is a type that can represent only two values: 0 and 1, usually identified with false and true respectively.

### Pascal (programming language)

PascalPascal programming languageISO 7185
In programming languages with a built-in Boolean data type, such as Pascal and Java, the comparison operators such as and are usually defined to return a Boolean value. This approach with boolean as a built-in (either primitive or otherwise predefined) data type was adopted by many later programming languages, such as Simula 67 (1967), ALGOL 68 (1970), Pascal (1970), Ada (1980), Java (1995), and C# (2000), among others. The language Pascal (1970) introduced the concept of programmer-defined enumerated types.

### Primitive data type

primitive typeprimitive typesprimitive
This approach with boolean as a built-in (either primitive or otherwise predefined) data type was adopted by many later programming languages, such as Simula 67 (1967), ALGOL 68 (1970), Pascal (1970), Ada (1980), Java (1995), and C# (2000), among others.
A boolean type, typically denoted "bool" or "boolean", is typically a logical type that can be either "true" or "false".

### Fortran

Fortran 77Fortran 90FORTRAN IV
The first version of FORTRAN (1957) and its successor FORTRAN II (1958) had no logical values or operations; even the conditional statement took an arithmetic expression and branched to one of three locations according to its sign; see arithmetic IF.
FORTRAN IV removed the machine-dependent features of FORTRAN II (such as READ INPUT TAPE), while adding new features such as a LOGICAL data type, logical Boolean expressions and the logical IF statement as an alternative to the arithmetic IF statement. FORTRAN IV was eventually released in 1962, first for the IBM 7030 ("Stretch") computer, followed by versions for the IBM 7090, IBM 7094, and later for the IBM 1401 in 1966.

### Enumerated type

enumerationenumsenumerations
The language Pascal (1970) introduced the concept of programmer-defined enumerated types.
The Boolean type, for example is often a pre-defined enumeration of the values False and True.

### C99

C99 programming language1999 standardC
Standard C (since C99) provides a boolean type, called.

### C Sharp (programming language)

C#Visual C#C# programming language
This approach with boolean as a built-in (either primitive or otherwise predefined) data type was adopted by many later programming languages, such as Simula 67 (1967), ALGOL 68 (1970), Pascal (1970), Ada (1980), Java (1995), and C# (2000), among others.
C# supports a strict Boolean data type,.

### C++

C++ programming languageC++98C with Classes
C++ has a separate Boolean data type, but with automatic conversions from scalar and pointer values that are very similar to those of C. This approach was adopted also by many later languages, especially by some scripting languages such as AWK.
Later feature additions included templates, exceptions, namespaces, new casts, and a boolean type.

### Null (SQL)

NULL NULLs
In SQL, which uses a three-valued logic for explicit comparisons because of its special treatment of Nulls, the Boolean data type (introduced in SQL:1999) is also defined to include more than two truth values, so that SQL Booleans can store all logical values resulting from the evaluation of predicates in SQL.
When restricted by a constraint, the SQL BOOLEAN works like the Boolean type from other languages.

### Lua (programming language)

LuaLua programming languageLuaJIT
Lua has a boolean data type, but non-boolean values can also behave as booleans.
It supports only a small number of atomic data structures such as boolean values, numbers (double-precision floating point and 64-bit integers by default), and strings.

### Python (programming language)

PythonPython programming languagePython 2
Python, from version 2.3 forward, has a type which is a subclass of, the standard integer type.

### Boolean differential calculus

boolean derivativeboolean differencePotential variable (Boolean differential calculus)
Boolean differential calculus (BDC) (German: Boolescher Differentialkalkül (BDK)) is a subject field of Boolean algebra discussing changes of Boolean variables and Boolean functions.

### C (programming language)

CC programming languageC language
Standard C (since C99) provides a boolean type, called. Initial implementations of the language C (1972) provided no Boolean type, and to this day Boolean values are commonly represented by integers ( s) in C programs.

### Literal (computer programming)

literalliteralsliteral constant
Although the SQL standard defines three literals for the BOOLEAN type – TRUE, FALSE, and UNKNOWN – it also says that the NULL BOOLEAN and UNKNOWN "may be used interchangeably to mean exactly the same thing".
Almost all programming languages have notations for atomic values such as integers, floating-point numbers, and strings, and usually for booleans and characters; some also have notations for elements of enumerated types and compound values such as arrays, records, and objects.

### PHP

PHP5PDOPHP programming language
Languages such as PHP also use this approach.
PHP has a native Boolean type that is similar to the native Boolean types in Java and C++.

### Computer science

computer scientistcomputer sciencescomputer scientists
In computer science, the Boolean data type is a data type that has one of two possible values (usually denoted true and false) which is intended to represent the two truth values of logic and Boolean algebra.

### Logic

logicianlogicallogics
In computer science, the Boolean data type is a data type that has one of two possible values (usually denoted true and false) which is intended to represent the two truth values of logic and Boolean algebra.