It is critical to distinguish between two types of PKG files:

In the context of the PlayStation 3, a (short for "package") is an installation archive similar to a .exe or .msi on Windows. Sony uses this format to distribute all digital content, including:

The PS3 DLC PKG is more than just a file format; it represents the community's successful effort to keep a generation of gaming history alive long after the original storefronts began to fade. technical steps

His PS3’s hard drive light flickered once, then went still.

When modding or managing a PlayStation 3 (PS3) serve as the standard digital container for installing applications, updates, and Downlaodable Content (DLC). Unlike disc-based folder structures, PKG files are self-contained and designed to be installed directly to the PS3’s internal hard drive via the Package Manager Ease of Use: 8/10

Inside the PKG, there is a table of contents (TOC) listing the files.