(1) The ability of equipment to be transported manually.
(2) The ability of a programme to run on more than one type of computer system without modification.
(3) The ability of a programming language to compile successfully on different operating systems without requiring changes to the source code.
(4) The ability to use Virtual Storage Access Method (VSAM) data sets with different operating systems. Volumes whose data sets are catalogued in a user catalogue can be removed from storage devices of one system, moved to another system, and mounted on storage devices of that system. Individual data sets can be transported between operating systems using access method services (AMS).