SIMH is a simulator for historical computer systems.

It supports, among others, the following platforms:

• Data General Nova and SuperNova
• DEC PDP-1, PDP-4, PDP-7, PDP-8, PDP-9, PDP-10, PDP-11, PDP-15 and VAX
• IBM 1401 and System 3
• HP 2100
• MITS Altair
• SDS 940