RPG
Report Program Generator, the primary business application programming language on IBM i and its AS/400 predecessors, still running the majority of production logic in most IBM i shops.
RPG has been the dominant IBM i application language since the AS/400 era. Most IBM i shops run a mix of older fixed-format RPG and newer free-format RPG, which is the core reason AI-assisted modernization tools like IBM Bob target RPG format conversion specifically.
Related Terms
Free-Format RPG
A modern RPG coding style that drops the rigid column-based syntax of traditional fixed-format RPG in favor of freer, more readable statement syntax.
IBM Bob (Project Bob)
IBM's generally available AI coding agent for IBM i, built as a fork of Visual Studio Code and tuned for RPG, CL, DDS, and SQL. Reached GA on March 24, 2026; Bob 2.0 and the IBM i-specific Bob Premium Package for i shipped June 24, 2026.
COBOL
A long-established business programming language still running production logic on IBM i and other legacy enterprise platforms alongside RPG.
IBM i
IBM's operating system for Power servers running traditional AS/400-lineage business applications, with Db2 for i built directly into the OS.