Etherpad is written in Javascript(99.9%) on both the server and client so it's easy for developers to maintain and add new features. Because of this Etherpad has tons of customizations that you can leverage.
that allows your web application to manage pads, users and groups. It is recommended to use the [available client implementations](https://github.com/ether/etherpad-lite/wiki/HTTP-API-client-libraries) in order to interact with this API.
There is also a [jQuery plugin](https://github.com/ether/etherpad-lite-jquery-plugin) that helps you to embed Pads into your website.
There's also a full-featured plugin framework, allowing you to easily add your own features. By default your Etherpad is rather sparse and because Etherpad takes a lot of it's inspiration from Wordpress plugins are really easy to install and update. Once you have Etherpad installed you should visit the plugin page and take control.
Additionally, you'll need [node.js](http://nodejs.org) installed, Ideally the latest stable version, we recommend installing/compiling nodejs from source (avoiding apt).
You can initially modify the settings in `settings.json`. (If you need to handle multiple settings files, you can pass the path to a settings file to `bin/run.sh` using the `-s|--settings` option. This allows you to run multiple Etherpad instances from the same installation.) Once you have access to your /admin section settings can be modified through the web browser.
You should use a dedicated database such as "mysql", if you are planning on using etherpad-in a production environment, since the "dirtyDB" database driver is only for testing and/or development purposes.
Etherpad is very customizable through plugins. Instructions for installing themes and plugins can be found in [the plugin wiki article](https://github.com/ether/etherpad-lite/wiki/Available-Plugins).
The [wiki](https://github.com/ether/etherpad-lite/wiki) is your one-stop resource for Tutorials and How-to's, really check it out! Also, feel free to improve these wiki pages.
If you want to find out how Etherpad's `Easysync` works (the library that makes it really realtime), start with this [PDF](https://github.com/ether/etherpad-lite/raw/master/doc/easysync/easysync-full-description.pdf) (complex, but worth reading).
Look at the [TODO list](https://github.com/ether/etherpad-lite/wiki/TODO) and our [Issue tracker](https://github.com/ether/etherpad-lite/issues). (Please consider using [jshint](http://www.jshint.com/about/), if you plan to contribute code.)
Join the [mailinglist](http://groups.google.com/group/etherpad-lite-dev) and make some noise on our busy freenode irc channel [#etherpad-lite-dev](http://webchat.freenode.net?channels=#etherpad-lite-dev)!