.pkg

Package of compressed installer files used to install a software program; commonly used for installing software in Mac OS X; may be installed individually or referenced by an installer script included with the software.

Double-click the package to install the files. Right-click (Control-click) and select "Show Package Contents" to view the files stored in the package. Apple Installer is the built-in utility for opening PKG files included with Mac OS X.

File downloaded from Sony's PlayStation Store, an online store with games, movies, and demos for PS3 and PSP devices; used specifically for downloadable games, game updates, and demos; saved in an encrypted format that is only recognized by compatible Sony devices.

Packages downloaded from the PlayStation Store can be transferred to a PSP or PS3 via USB, Memory Stick, or a network connection.