AS/400
From MidrangeWiki
The original name for the ISeries still in use by many programmers and administrators. First sold in 1988 it was the direct successor to the System/38.
The original AS/400 hardware was based on a 48bit CISC CPU, but was replaced with a 64bit RISC CPU. Even though the hardware platform changed, very few programs needed to be changed or even recompiled.
