TRaSH-Guides/includes/sonarr/imdb-vs-tvdb.md

While both IMDb and TVDb IDs are unique, TVDb can occasionally remove IDs entirely, sometimes only to be re-added with a new ID later. However, due to using TVDb as its metadata source, they can be seen as "more aligned" with Sonarr. IMDb IDs on the other hand, once present, are very accurate and rarely ever change.