The Free On-line Dictionary of Computing (30 December 2018):
The leading family of games consoles, from
Sony Corporation consisting of the original Playstation
(PS1) and the Playstation 2 (PS2).
The basic Playstations consist of a small box containing the
processor and a DVD reader, with video outputs to connect to
a TV, sockets for two game controllers, and a socket for one
or two memory cards. The PS2 also has USB sockets.
The PS2 can run PS1 software because the PS2's I/O processor
is the same as the PS1's CPU.