AIX is short for Advanced Interactive eXecutive.
AIX is the UNIX operating system from IBM for RS/6000, pSeries and the latest p5 & p5+ systems. Currently, it is called "System P". AIX/5L the 5L addition to AIX stands for version 5 and Linux affinity. AIX and RS/6000 was released on the 14th of February, 1990 in London.
Currently, the latest release of AIX is version 6.
AIX 7 beta will be released in Aug 2010, along with the new POWER7 hardware range.
Today IBM Pureflex is