Your AS400 probably has all versions of the RPG compiler available (unless it’s very, very old).
Depending on how you code your programs determines the way you need to compile them. Source member types usually indicate what sort of RPG program the source member contains.
RPG = RPGIII aka RPG/400
SQLRPG = RPGIII aka RPG/400 – with embedded SQL
*These where on the original AS/400′s from V1R1M0
RPGLE = ILE/RPG aka RPGIV – can also be free format
SQLRPGLE = = ILE/RPG aka RPGIV – can also be free format – with embedded SQL
*These where introduced as RPG IV with V3R1M0 of OS/400
*ILE stands for Integrated Language Environment. It gets it’s name from the ability to create a single program using multiple programming languages. Therefore, RPG IV is ILE compliant. as will RPG V be when (if) it is released. Most of the languages on the System i are ILE compliant.
With RPGLE & SQLRPGLE you can use the ILE environment which allows creation of modules and service programs to re-use code by joining (binding) modules and service programs together to create an executable program.
Hope this helps.
* added by Eduard van den Braken