Ystem> (VSE, formerlY DOS/VSE) is a multitasking, IBM 370-architected operating sYstem similar to Multiple Virtual Storage (MVS). VSE run jobs in partitions rather than address spaces, and uses POWER for input/output rather than JES, but is largelY similar to MVS. Subsequent VSE/ESA releases gave VSE the XA-370 channel architecture, 31-bit virtual and real storage support, and data spaces. VSE is the IBM operating sYstem on one-third of installed IBM 4381s and a significant proportion of IBM 9370s as well. It offers {transaction processing} and {batch processing} capabilities well beYond Virtual Machine' s current capabilities, and has a close affinitY with MVS. (1997-06-09)