What does PS stand for in PS/2?

Question

PS/2

Anyone knows?

Answer 1

IBM Personal System 2.

The Personal System/2 or PS/2 was IBM's third generation of personal computers. The PS/2 line, released to the public in 1987, was created by IBM in an attempt to recapture control of the PC market by introducing an advanced proprietary architecture.

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PS/2 systems introduced a new specification for the keyboard and mouse interfaces, which are still in use today and are thus called "PS/2" interfaces.

Answer 2

As Michael Petrotta mentioned it is the Personal System/2 from IBM which defined the new "Standard" as a time when proprietary connections were the standard.

http://computer-engineering.org/ps2protocol/

IBM introduced a new keyboard with each of its major desktop computer models. The original IBM PC, and later the IBM XT, used what we call the "XT keyboard." These are obsolete and differ significantly from modern keyboards; the XT keyboard is not covered in this article. Next came the IBM AT system and later the IBM PS/2. They introduced the keyboards we use today, and are the topic of this article. AT keyboards and PS/2 keyboards were very similar devices, but the PS/2 device used a smaller connector and supported a few additional features. Nonetheless, it remained backward compatible with AT systems and few of the additional features ever caught on (since software also wanted to remain backward compatible.) Below is a summary of IBM's three major keyboards.