{{fbdoc item="title" value="BOOLEAN"}}----
Standard data type

{{fbdoc item="syntax"}}##
	[[KeyPgDim dim]] //variable// [[KeyPgAs as]] **Boolean**
##
{{fbdoc item="desc"}}
	Boolean data type. Can hold the values ##[[KeyPgTrue True]]## or ##[[KeyPgFalse False]]##.

	**Notes on definition of boolean data type:** //Ideally, the definition of the boolean data type is that it holds the value of ##[[KeyPgTrue True]]## or ##[[KeyPgFalse False]]##, and that's it.  However, to make this concept a reality, we need a definition that uses real world connections.  A more realistic definition is that the boolean data type is a 1-bit integer, having the value 0 to indicate ##[[KeyPgFalse False]]## and 1 to indicate ##[[KeyPgTrue True]]##.  For a practical definition, we must consider, yet again, additional factors.  The most significant factor is that the hardware (processor) on which code is executed does not directly support a 1-bit data type; the smallest register or memory size we can work with is 8-bits or 1-byte.  Therefore, a practical definition of boolean data type is an integer, 8 bits wide, having the value 0 or 1, where all other values are undefined.  However, because of longstanding differences between C/C""++"" and FB with respect to logical operations, the interpretation of the value must also be considered.  Assume "false" is 0 in both C/C""++"" and FB.  C/C""++"" has logical 'not' operator '!' such that '!0' produces '1'.  FB has a bitwise ##[[KeyPgOpNot Not]]## operator such that 'not 0' produces '-1'.  Therefore the definition for a C/C""++"" boolean is an unsigned 1-bit integer, zero extended to fill larger integer types, and the definition for a FB boolean is a signed 1-bit integer, sign extended to fill larger integer types.  However, the purpose and intent of the boolean data type remains, that it should only ever hold a ##[[KeyPgTrue True]]## value or ##[[KeyPgFalse False]]## value, regardless of the underlying details.//

{{fbdoc item="ex"}}
{{fbdoc item="filename" value="examples/manual/datatype/boolean.bas"}}%%(freebasic)
Dim boolvar As Boolean
boolvar = True
Print "boolvar = ", boolvar
%%
**Output:**
	%%boolvar =     true%%

{{fbdoc item="lang"}}
	- Not available in the //[[CompilerOptlang -lang qb]]// dialect unless referenced with the alias ##**""__Boolean""**##.

{{fbdoc item="diff"}}
	- New to ""FreeBASIC""

{{fbdoc item="see"}}
	- ##[[KeyPgTrue True]]##
	- ##[[KeyPgFalse False]]##

{{fbdoc item="back" value="CatPgStdDataTypes|Standard Data Types"}}