Etherpad is a real-time collaborative editor [scalable to thousands of simultaneous real time users](http://scale.etherpad.org/). It provides [full data export](https://github.com/ether/etherpad-lite/wiki/Understanding-Etherpad's-Full-Data-Export-capabilities) capabilities, and runs on _your_ server, under _your_ control.
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.
Similarly, `--credentials` can be used to give a settings override file, `--apikey` to give a different APIKEY.txt file and `--sessionkey` to give a non-default SESSIONKEY.txt.
**Each configuration parameter can also be set via an environment variable**, using the syntax `"${ENV_VAR}"` or `"${ENV_VAR:default_value}"`. For details, refer to `settings.json.template`.
If you are planning to use Etherpad in a production environment, you should use a dedicated database such as `mysql`, since the `dirtyDB` database driver is only for testing and/or development purposes.
If you have enabled authentication in `users` section in `settings.json`, it is a good security practice to **store hashes instead of plain text passwords** in that file. This is _especially_ advised if you are running a production installation.
Please install [ep_hash_auth plugin](https://www.npmjs.com/package/ep_hash_auth) and configure it.
If you prefer, `ep_hash_auth` also gives you the option of storing the users in a custom directory in the file system, without having to edit `settings.json` and restart Etherpad each time.
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).
You can run Etherpad quickly launching `bin/fastRun.sh`. It's convenient for developers and advanced users. Be aware that it will skip the dependencies update, so remember to run `bin/installDeps.sh` after installing a new dependency or upgrading version.
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).
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.
Etherpad offers a plugin framework, allowing you to easily add your own features. By default your Etherpad is extremely light-weight and it's up to you to customize your experience. Once you have Etherpad installed you should [visit the plugin page](https://static.etherpad.org/) and take control.