than z/OS and is mostly used on smaller machines. DOS/VSE was introduced in 1979 as a successor to DOS/VS; in turn, DOS/VSE was succeeded by VSE/SP version
z/OS, z/VSE, z/TPF, and z/VM are versions of MVS, VSE, Transaction Processing Facility (TPF), and VM that support z/Architecture. Older versions of z/OS
DOS/VSEVSE/SP (program product including DOS/VSE and VSE/AF) VSE/ESA, replaces VSE/SP, supports ESA/370 and ESA/390 with 31-bit addresses z/VSE (latest