Plays
Plays is the service type sold for audio platforms, where the unit is one playback of a track rather than a view of a video or a visit to a profile.
The link is a track, album or playlist address, and the format matters more than on most services: platforms hand out several link styles for the same track, and suppliers usually accept only one. Get it wrong and the order is charged before anyone discovers the problem. Some services also ask you to confirm the track is publicly available in the regions the delivery comes from.
Plays are slow by construction. A play only counts once it has run for a minimum length the platform sets, so the supplier has to hold each stream open for real time rather than pinging a counter. That caps how fast an order can move and explains why a play service can take days to finish a quantity a like service would clear in an hour. Playback cut short may register as nothing at all.
The payout side is where this service differs most from the rest of a catalogue. Platforms review streaming activity, discount or remove streams they judge to be artificial, and can take action against the release or the distributor rather than just declining to pay. Those decisions happen after delivery, in a dashboard the panel cannot read, and the platform's rules change. Treat a play count in the public interface and a stream in a royalty statement as two separate numbers.
Playbacks and listeners
A playback is not a listener. A service that delivers a quantity of playbacks says nothing about how many distinct accounts were involved, whether anyone heard the track through, or whether the platform will count any of it toward payouts or its own recommendation systems.