V.E.R.A. -- Virtual Entity of Relevant Acronyms (February 2016):

PS2
       Personal System /2, "PS/2"


The Free On-line Dictionary of Computing (30 December 2018):

PS/2

    IBM's second generation of personal computers.
   The PS/2 series introduced three advances over the PC series:
   3.5" 1.44 megabyte microfloppy disks, VGA and 8514
   graphics display standards, and the Micro Channel bus
   architecture.  The 3.5" disks and VGA can be easily installed
   on other PCs and will become the standard for new compatible
   computers.  The Micro Channel bus allows for multiprocessing
   and less aggravation, but cannot be retrofitted to older PCs.

   PS/2 models 25 and 30 are ISA, other models have Micro
   Channel and ESDI.

   (1995-11-27)