Canonical records

Media pulls from a dozen sources. Each has its own identifiers, its own spelling, and its own idea of what counts as an album.

A canonical record is Media's own identity for an artist, album or track, with every source's version mapped onto it.

Why it matters

Without it, "how many times have I played this album" is unanswerable: Plex has one album, Last.fm has scrobbles against a slightly different title, Discogs has three pressings, and none of them share a key.

With it, they are one album, and the question has an answer.

What follows from it

Counts are per canonical, not per source. Two pressings of the same record are one album in your library.

A source going away does not delete the record. Removing a Spotify link removes Spotify's contribution, not the album.

Matching is not infallible. Two genuinely different releases can be merged, and one release can fail to match itself across sources. The Administration section has a Duplicates view for exactly this, because it is a real and recurring problem rather than a theoretical one.

Linked versus playable

Two different facts that are easy to conflate:

Plex linked	Media knows which Plex item this canonical corresponds to
Plex playable	That Plex item currently exists and can be played

An album can be linked and not playable — the file moved, the library was rescanned, the server is down. The library view distinguishes them because "we know about it" and "you can hear it right now" are different questions.