* [One Language Code](#language)

10. <a name="language">One Language Code</a>

JavaScript needs to be written in one language as their native instructions are already in English.

Even if you have any difficulty in speaking or writing English, you may struggle a bit to maintain the readability of your code.

This principle is even more important in an Open Source project. This way you should consider comments as well.

Notice that variable contents are not included in this rule in small or specific projects, but you should consider [localization](https://en.wikipedia.org/wiki/L10n) in bigger or Open Source projects.

```javascript

// Bad

function calculaValor(arg1, arg2) {

var retorno = arg1 + arg2;

return retorno;

}

// Good

console.log('Hello World');

// Good as well

console.log('Oi Mundo');

```