# Truthy and Falsy Values in Javascript

In Javascript, things can be `true`, or `false`, but they can also be `truthy` or `falsy`. The concept of `truthy` and `falsy` are usually considered only in a boolean context, such as in an `if..else` statement, but they also affect other parts of Javascript - for example, what is returned from the [logical OR operator](https://fjolt.com/article/javascript-logical-or).

## What does truthy and falsy mean in Javascript?
Something is considered `falsy` in Javascript if it can be converted to `false`. In the same way, something is `truthy` simply if it is not considered `falsy`. While `falsy` may seem like a vague statement, it actually has a specific definition. The following values are considered `falsy`:

- `false`
- `0` or `-0` or `0n`
- any empty string, i.e. `""`
- `null`
- `undefined`
- `NaN`

Similarly, anything that is not equal to these is considered `truthy`, for example:

- any object, i.e. `{}`, or `[]`.
- any non-zero number
- any non-empty string
- any non `null`, `undefined`, or `NaN` value.

## Use of truthy and falsy 

`truthy` and `falsy` values have implications in Javascript logic. For example, anything that can be converted to `truthy` in a boolean setting (such as `if..else`) is converted to `true`, and the same goes for `falsy` statements.

For example, the following `if` statement is `true`, simply because `"1"` is a `truthy` statement:

```javascript
if("1") {
    console.log('ok');
}
```

If the statement instead said `if(0)`, it would return false, since `0` is `falsy`. As you get into Javascript, you'll find references to `truthy` and `falsy` everywhere, so it's good to familiarise yourself with the concept now.