In the context of gaming, ROMs are copies of games stored on a physical chip in arcade machines and older consoles. For modern gaming on consoles like the PS4, the term often relates to pirated copies or updates. However, for legitimate players, updates are managed through the PlayStation Store.
PKG files are used by the PlayStation to package and distribute games and updates. When you buy or update a game on the PlayStation Store, it downloads a PKG file to your console, which then installs the game or update.
Some notable DLCs for Resident Evil 4 Remake include:
