This IBM Support page has the latest information on IBM i group PTFs and recommended fixes.
This IBM Support page documents all the IBM i releases with key dates, such as announcement, GA, and withdrawal dates.
This IBM Support document answers many questions about MTIs.
This IBM web site has information about RPG enhancements and other RPG-related topics.
The “IBM i Power External Storage Support Matrix Summary” provides you with a quick summary of all IBM supported external storage and how it can be used on IBM i.