First released on March 30, 2001 as the successor to its OS/390 operating system, z/OS is a 64-bit operating system developed by IBM for IBM’s z/Architecture line of mainframe computers.
Benefits of z/OS
Most modern computers have a 2 GB limit on the amount of memory that can be addressed in actual program code. However, z/OS uses a customized implementation of Java that allows for a theoretical maximum of 16 exabytes or more than 8 billion times that of a typical computer.
64-bit, Architecture, IBM, Mainframe, Memory, Operating System terms