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Microsoft MakeCode, also known as Programming Experience Toolkit (PXT), provides Blocks / JavaScript tools and editors

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# Boolean A Boolean has one of two possible values: `true` or `false`. Boolean (logical) operators (*and*, *or*, *not*) take Boolean inputs and make another Boolean value. Comparison operators on other types ([numbers](/types/number), [strings](/types/string)) create Boolean values. These blocks represent the `true` and `false` Boolean values, which can plug into anyplace a Boolean value is expected: ```block let on = true; ``` The next three blocks represent the three Boolean (logic) operators: ```block let and = true && false; let or = true || false; let not = !true; ``` The next six blocks represent comparison operators that yield a Boolean value. Most comparisons you will do involve [numbers](/types/number): ```block let equality = 42 == 42; let inequality = 42 != 42; let lowerThan = 42 < 0; let greaterThan = 42 > 0; let lowerOrEqualThan =42 <= 0; let greaterOrEqualThan = 42 >= 0; ``` Boolean values and operators are often used with an [if](/blocks/logic/if) or [while](/blocks/loops/while) statement to determine which code will execute next. For example: ## Functions that return a Boolean Some functions return a Boolean value, which you can store in a Boolean variable. For example, the following code gets the on/off state of `point (1, 2)` and stores this in the Boolean variable named `on`. Then the code clears the screen if `on` is `true`: ## Boolean operators Boolean operators take Boolean inputs and evaluate to a Boolean output: ## Conjunction: `A and B` `A and B` evaluates to `true` if-and-only-if both A and B are true: ```block let off = false && false; let off2 = false && true; let off3 = true && false; let on = true && true; ``` ## Disjunction: `A or B` `A or B` evaluates to `true` if either `A` is true or `B` is true, or if both `A` and `B` are true: ```block let off = false || false; let on = false || true; let on2 = true || false; let on3 = true || true; ``` ## Negation: `not A` `not A` evaluates to the opposite (negation) of A: ```block let on = !false; let off = !true; ``` ## #examples