Update README

README.md

@@ -1,6 +1,43 @@
+# ES6 `Number.isNaN` polyfill
+
+A polyfill for [the `Number.isNaN` method in ECMAScript 6](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-number.isnan).
+
+Other polyfills for `Number.isNaN` are available:
+
+* <https://github.com/ljharb/is-nan> by [Jordan Harband](https://twitter.com/ljharb)
+* <https://github.com/paulmillr/es6-shim/blob/0.10.1/es6-shim.js#L726-L733> by [Paul Miller](http://paulmillr.com/)
+
+## Installation
+
+In a browser:
+
+```html
+<script src="isnan.js"></script>
+```
+
+Via [npm](http://npmjs.org/):
+
+```bash
+npm install number.isnan
+```
+
+Then, in [Node.js](http://nodejs.org/):
+
+```js
+require('number.isnan');
+
+// On Windows and on Mac systems with default settings, case doesn’t matter,
+// which allows you to do this instead:
+require('Number.isNaN');
+```
+
 ## Relevant links
 
 * https://people.mozilla.org/~jorendorff/es6-draft.html#sec-number.isnan
 * http://wiki.ecmascript.org/doku.php?id=harmony:number.isnan
 * http://ariya.ofilabs.com/2014/05/the-curious-case-of-javascript-nan.html
 * http://www.2ality.com/2012/02/nan-infinity.html
+
+## License
+
+MIT License