It seems that some of the browsing operations can be performed either on USB devices or on discs, while others can only be performed on one or the other. Tell me exactly what can be done on USB devices and what can be done on discs.

On USB devices, in addition to folder browsing, library browsing is also possible on CDJs for which the library is created ahead of time with rekordbox.

Library browsing is a function allowing you to select and search for files by category (album, artist, track, playlist, history, etc.) specified with rekordbox or by sorting order. With discs, only folder browsing is possible.