---
url: /docs/guide/usage/linter/rules/eslint/no-restricted-globals.md
---

### What it does

Specify global variable names that should not be used in your application.

### Why is this bad?

Disallowing usage of specific global variables can be useful if you want to allow a set of global
variables by enabling an environment, but still want to disallow some of those.

For instance, early Internet Explorer versions exposed the current DOM event as a global variable
`event`, but using this variable has been considered as a bad practice for a long time. Restricting
this will make sure this variable isn't used in browser code.

### Examples

If we have options:

```json
"no-restricted-globals": ["error", "event"]
```

The following patterns are considered problems:

```javascript
function onClick() {
  console.log(event); // Unexpected global variable 'event'. Use local parameter instead.
}
```

## How to use

## Version

This rule was added in v0.4.0.

## References