Software designed to perform a specific set of functions.

An interactive application generally refers to a computer program that is downloaded to execute on the set-top box.

The application and associated data may be transmitted in-band as part of the broadcast signal or downloaded on demand out-of-band over the return path.

A broadcast application is typically transmitted continuously in a carousel so that it is available whenever a user tunes to a channel and selects the service. The cycle time or repeat frequency will determine the time taken to access an application and is generally limited to a few seconds.

Some applications may use the return path to retrieve additional data or return a response.

Where the return path is continuously available, as in the case of cable systems, the application or associated data may be retrieved on request, rather like a web service.