# 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, strings) create Boolean values.

These blocks represent the `true` and `false` Boolean values, which can plug into anyplace a Boolean value is expected:

``````true;
false;``````

The next three blocks represent the three Boolean (logic) operators:

``````true && false;
true || false;
!true;``````

The next six blocks represent comparison operators that yield a Boolean value. Most comparisons you will do involve numbers:

``````42 == 0;
42 != 0;
42 < 0;
42 > 0;
42 <= 0;
42 >= 0;``````

Boolean values and operators are often used with an if or 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:

``````false && false == false;
false && true == false;
true && false == false;
true && true == true;``````

### Disjunction: `A or B`

`A or B` evaluates to `true` if-and-only-if either A is true or B is true:

``````false || false == false;
false || true == true;
true || false == true;
true || true == true;``````

### Negation: `not A`

`not A` evaluates to the opposite (negation) of A:

``````!false == true;
!true == false;``````

## Example: `AND` operator

This example turns on LED `3 , 3`, if LEDs `1 , 1` and `2 , 2` are both on:

``````if (led.point(1,1) && led.point(2,2)) {
led.plot(3,3)
}``````

## Example: Comparisons of numbers and strings

When you compare two Numbers, you get a Boolean value, such as the comparison `x < 5` in the code below:

``````input.onButtonPressed(Button.A, () => {
let x = Math.random(5)
if(x < 5) {
basic.showString("low");
} else {
basic.showString("high");
}
})``````

See the documentation on Numbers for more information on comparing two Numbers.