Consider a formal algebraic specification for the boolean data type.

This is because the Boolean data type is stored as a 16-bit signed integer.

JavaScript provides a Boolean data type with and literals.

Boolean - The Boolean data type has only two possible values: true and false or 1 and 0.

Objective-C also has a separate Boolean data type (), with possible values being or , equivalents of true and false respectively.

Languages without an explicit Boolean data type, like C90 and Lisp, may still represent truth values by some other data type.

Alternatively, the entire system of boolean data types could be specified using a different set of constructor functions: a false constructor and a not constructor.

The Boolean data type is the primary result of conditional statements, which allow different actions and change control flow depending on whether a programmer-specified boolean condition evaluates to true or false.

For example, the designers of Ada and Java were so worried about this type of mistake, they restricted control expressions to those that evaluate strictly to the boolean data type.

In programming languages that have 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 Java, these operators return true or false, depending on whether the conditional relationship between the two operands holds or not.

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 ones such as AWK.