# Captivate Controller Setup

Many of Captivate's built-in controllers use JavaScript embedded in HTML pages to drive data to the application. Captivate's embedded browser hosts the HTML page as a user interface to the controller and the JavaScript code connects to the Captivate WebSocket API to schedule data and playback operations on titles.

Using this method, any data that can be entered by a user, accessed from the web, or read from a file can be pulled into Captivate, translated into variables by JavaScript, and sent back to the Captivate scheduler.

For convenience, Captivate includes a built-in HTTP server to optionally host your HTML pages, making it even easier to create your own simple controllers.

> **Note:** For definitions of the different terms, controller, input, and title, please see the [Terminology](/getting-started/terminology.md) page. For detailed explanation of our API, please see the [Controller API Reference Page.](/captivate-api/javascript-api-reference.md)


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