Editing Job Entry Subsystem 2/3 (section)

==== HASP ====
{{Main|Houston Automatic Spooling Priority}}
HASP was developed by IBM Federal Systems Division contractors at the [[Johnson Space Center]] in [[Houston]].<ref name=HASPIIV3M1/><ref name=GC27-0052/> It originally managed job scheduling and print and punch output for a single OS/360 computer. ''Multi Access Spool'' capability was added to let peer computers share a common job queue and print/punch output queues.{{citation needed|date=May 2018}}

With the introduction of [[IBM System/370|System/370]] in 1972, IBM rewrote HASP to become a standard part of the system and renamed it ''Job Entry Subsystem 2''. JES2 was introduced in OS/VS2 in Release 2, also known as [[MVS]], in 1973.<ref name=VS2Intro/> It was many years before the HASP labels were removed from the source code, and the messages issued by JES2 are still prefixed with <code>$HASP</code>.  Several JES2 commands continue to support specification of either <code>JES2</code> or <code>HASP</code> to maintain [[backwards compatibility]].<ref name=jes-deathmatch-2018-april/>