A PCK file is a package created with Oracle PL/SQL database software, most notably Allround Automations PL/SQL Developer. It contains a package specification and package in the PL/SQL language. PCK files are used to define the stored public procedures, functions, types, etc. that can be accessed by other applications to prevent package data from being unintentionally modified.

You can open and edit PCK files using PL/SQL Developer, which is developed by Allround Automations. You can also view and edit a PCK with a text editor since it is stored in plain text. The PCK file allows you to combine the specifications for a PL/SQL package and the package body into one file. Typically, the specifications and body are stored in separate files. The package specification, which declares the variables, exceptions, types, constants, cursors, and subprograms publicly accessible from other applications, is commonly stored in the .PKS file. The package body, which consists of the code that implements the procedures, functions, and cursors listed in the package specification, is commonly stored in the .PKB file. NOTE: PL/SQL is a procedural language extension to Structured Query Language (SQL). It is available in Oracle Database (since version 6), IBM DB2 (since version 9.7), and TimesTen in-memory database (since version 11.2.1).

Game data file used by Perfect World, a free massively multiplayer online role-playing (MMORPG) game; may contain various game data, including world information and avatar, item, and building models; used for game installations and updates.

File used by System Center Configuration Manager (SCCM), an application used to administer large groups of Windows computer systems; contains an update package, which can store system and application files; used for updating client systems.

To distribute PCK files, the SCCM software first builds a compressed PCK file with the source files for the update and then sends it to a Distribution Point (DP) computer. The DP allows registered client computers to download available packages in order to update their software. NOTE: SCCM was previously called Systems Management Server (SMS) in versions 2003 and earlier.