# 
> Terminal string styling done right
[](https://travis-ci.org/sindresorhus/chalk)
[colors.js](https://github.com/Marak/colors.js) is currently the most popular string styling module, but it has serious deficiencies like extending String.prototype which causes all kinds of [problems](https://github.com/yeoman/yo/issues/68). Although there are other ones, they either do too much or not enough.
**Chalk is a clean and focused alternative.**
## Why
- Highly performant
- Doesn't extend String.prototype
- Expressive API
- Ability to nest styles
- Clean and focused
- Auto-detects color support
- Actively maintained
- [Used by 1000+ modules](https://npmjs.org/browse/depended/chalk)
## Install
```sh
$ npm install --save chalk
```
## Usage
Chalk comes with an easy to use composable API where you just chain and nest the styles you want.
```js
var chalk = require('chalk');
// style a string
console.log( chalk.blue('Hello world!') );
// combine styled and normal strings
console.log( chalk.blue('Hello'), 'World' + chalk.red('!') );
// compose multiple styles using the chainable API
console.log( chalk.blue.bgRed.bold('Hello world!') );
// pass in multiple arguments
console.log( chalk.blue('Hello', 'World!', 'Foo', 'bar', 'biz', 'baz') );
// nest styles
console.log( chalk.red('Hello', chalk.underline.bgBlue('world') + '!') );
// nest styles of the same type even (color, underline, background)
console.log( chalk.green('I am a green line ' + chalk.blue('with a blue substring') + ' that becomes green again!') );
```
Easily define your own themes.
```js
var chalk = require('chalk');
var error = chalk.bold.red;
console.log(error('Error!'));
```
Take advantage of console.log [string substitution](http://nodejs.org/docs/latest/api/console.html#console_console_log_data).
```js
var name = 'Sindre';
console.log(chalk.green('Hello %s'), name);
//=> Hello Sindre
```
## API
### chalk.`