# undefined value

The `undefined` value stands for "undefined". JavaScript has a similar `null` value that denotes the absence of a value. The difference is that `null` denotes an intentional absence (explicitly written in a code), while `undefined` is simply the absence of any information about the element type and its value.

## Syntax

`undefined;`

## Example

Let's find out the variable value that was declared without a value:

`let test; console.log(test);`

The code execution result:

`undefined`

## Example

Let's find out the value of a non-existent array element:

`let arr = ['a', 'b', 'c']; console.log(arr[5]);`

The code execution result:

`undefined`

## Example

Let's find out the value of a non-existent object element:

`let obj = {'a': 1, 'b': 2, 'c': 3}; console.log(obj['e']);`

The code execution result:

`undefined`

## See also

- the `true` value
  that indicates that the element value is true
- the `false` value
  that indicates that the element value is false
- the `null` value
  that denotes the absence of an object or element

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