# Boolean function

The `Boolean` function converts a passed value to a boolean. The result of the function execution will be either `true`, or `false`.

In this case, only the following are converted to `false`: `0`, an empty string, `null`, `undefined`, `NaN`. All other values (numbers, strings, objects, arrays, functions) are converted to `true`.

## Syntax

`Boolean(what to convert);`

## Example

Let's convert the number `0` to a boolean type:

`Boolean(0);`

As a result of executing the code, we will get `false`:

`false`

## Example

Let's convert the `NaN` value:

`Boolean(NaN);`

Also after executing the code we get `false`:

`false`

## Example

Now let's convert the number `1`:

`Boolean(1);`

After executing the code, we get `true`:

`true`

## Example

Now let's convert a negative number:

`Boolean(-1);`

As a result of executing the code, we will get `true`:

`true`

## Example

Let's set a parameter to a fractional number:

`Boolean(11.5);`

After executing the code, we will also get `true`:

`true`

## Example

Now let's convert an empty string:

`Boolean('');`

The code execution result:

`false`

## Example

If we enter a filled string in the parameter:

`Boolean('str');`

Then after conversion we get `true`:

`true`

## Example

Let's convert the boolean `true` value:

`Boolean(true);`

The code execution result:

`true`

## Example

Now let's convert the boolean `false` value:

`Boolean(false);`

As a result of executing the code, `false` is returned to us:

`false`

## Example

Let's specify an empty object in the function parameter:

`Boolean({});`

After executing the code, the `Boolean` function will convert the object to the `true` value:

`true`

## Example

Now we specify an empty array in the parameter:

`Boolean([]);`

After executing the code, we will also get the `true` value:

`true`

## Example

Let's convert an empty function:

`Boolean(function(){});`

As a result of code execution, we get `true`:

`true`

## Example

Now let's convert the `null` value:

`Boolean(null);`

As a result of the code execution, we get `false` as well as when converting the number `0`:

`false`

## See also

- the `Number` function
  that converts to a number
- the `String` function
  that converts to a string

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