Headend vs. Lineup

A headend may contain multiple lineups, and a lineup is a specific mapping of channels and stationIDs.

You may have an analog lineup, meaning the channels that you can tune using an analog tuner. In a cable lineup, this would be channels "2" through "125". In the data, these are typically called "DEFAULT".

You may have a digital lineup; one that requires an external set-top-box. For a cable lineup, most digital lineups are designated with an "X" as the device for historical reasons.

You may have a QAM lineup; cable TV content which is available with a QAM tuner. The device type would be "QAM".