The System i five-layer cake: Yum

IBM i Chief Architect Steve Will has a post describing the five integral layers of the System i operating system, formerly called i5/OS. They are:

1. Integrated Middleware
2. “The” Operating System
3. Technology Independent Machine Interface
4. Licensed Internal Code
5. Hypervisor

Will sums it up at the end:

In summary, the robust IBM i operating system is flexible and long-lived largely due to this layered architecture. When we talk about IBM i, we’re talking about all of these layers in combination. I hope this brief introduction helps you understand the value that comes to you when you run IBM i, and why the IBM i development team continues to work hard to bring you this great integrated operating system.