A stored procedure on the AS/400 is created in any SQL environment (CREATE PROCEDURE).
This is a permanent object and like C objects it is recognized by it's name and parameters.
Is callable from any SQL environment.
Defines the variables to be passed in and returned and return sets.
Can contain a body of SQL commands
Can reference a native language pgm (RPGLE, CL, CLLE, CBLLE)
These are most frequently used to support external programs (VB, Java, etc.)
Here are a few sites located with AS/400 Stored Procedures - hundreds more.