# Stand-alone Application

Essentials was originally designed as a standalone SIMPL# Pro control system application and has developed into a versatile, pluggable application. This page describes how to use our built-in room types for a completely self-contained "one-slot" control program.

By defining devices and a room in a JSON configuration file, Essentials can control an entire AV control system for a room. A file can be manually created in an IDE such as Visual Studio Code, or it can be generated by a friendly web-based configuration tool on [PepperDash Portal](http://pepperdash.com/products/), or some other configuration tool application, both requiring no knowledge of JSON.  These tools step a user through building the necessary devices and setting to achieve a full working room.

## Plugins

### Devices

Essentials supports device plugins for communicating with various devices using both standard Crestron CIP communications, Cresnet, SSH, or other TCP/IP-based communication methods. See [the Plugins section](~/docs/technical-docs/Plugins.md) for more details

### Rooms

In order to tie together equipment into a unit that comprises what devices are used in a room, Essentials supports Room plugins. These plugins are similar to device plugins, in that they're loaded at runtime and allow for customization of business logic and behavior. They're loaded into a different section of the Device Manager, and can reference devices created by device plugins using the device's key.

See Also: [[Supported Devices|Supported-Devices]]

Next: [Simpl Windows bridging](~/docs/usage/SIMPL-Bridging-Updated.md)
