Update readme.

Author: goto-bus-stop

readme.markdown

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-# path-browserify
+# path-browserify [![Build Status](https://travis-ci.org/browserify/path-browserify.png?branch=master)](https://travis-ci.org/browserify/path-browserify)
 
-the path module from node core for browsers
+> The `path` module from Node.js for browsers
+
+This implements the Node.js [`path`](http://nodejs.org/api/path.html) module for environments that do not have it, like browsers.
+
+> `path-browserify` currently matches the **Node.js 10.3** API.
+
+## Install
+
+You usually do not have to install `path-browserify` yourself! If your code runs in Node.js, `path` is built in. If your code runs in the browser, bundlers like [browserify](https://github.com/browserify/browserify) or [webpack](https://github.com/webpack/webpack) include the `path-browserify` module by default.
+
+But if none of those apply, with npm do:
+
+```
+npm install path-browserify
+```
+
+## Usage
+
+```javascript
+var path = require('path')
+
+var filename = 'logo.png';
+var logo = path.join('./assets/img', filename);
+document.querySelector('#logo').src = logo;
+```
+
+## API
+
+See the [Node.js path docs](http://nodejs.org/api/path.html). `path-browserify` currently matches the Node.js 10.3 API.
+`path-browserify` only implements the POSIX functions, not the win32 ones.
+
+## Contributing
+
+PRs are very welcome! The main way to contribute to `path-browserify` is by porting features, bugfixes and tests from Node.js. Ideally, code contributions to this module are copy-pasted from Node.js and transpiled to ES5, rather than reimplemented from scratch. Matching the Node.js code as closely as possible makes maintenance simpler when new changes land in Node.js.
+This module intends to provide exactly the same API as Node.js, so features that are not available in the core `path` module will not be accepted. Feature requests should instead be directed at [nodejs/node](https://github.com/nodejs/node) and will be added to this module once they are implemented in Node.js.
+
+If there is a difference in behaviour between Node.js's `path` module and this module, please open an issue!
+
+## License
+
+[MIT](./LICENSE)