NEC M-System keyboards History

In 1983, NEC 日本電気 came out with a new keyboard and new Japanese input system, called M-system (M式), designed by Dr. Masasuke Morita at NEC.

M-system is 2 things:

1. A physical keyboard design that has 4 or more thumb keys, and symmeric (typically have dedicated sections for left hand and hand).
2. A efficient Japanese input system. It's a romanji input system. (you type English Letter then convert to kata (Japanese alphabet)) The English letter arrangement is optimized for kana.

Over the years, there are several M-system keyboard designs. Here's a list of them.

• 
  NEC PC-8801-KI, 1983

• 
  NEC 文豪 Mini7, 1985

• 
  NEC M-system, 1990

• 
  NEC 文豪 Mini7RM, 1992

• 
  NEC PC-9801, 1992

• 
  NEC Ergofit, 1998

Reference

• [【NEC】 Keyboard based on new input system (M system) 2013-01-21 By Information Processing Society Of Japan. At http://museum.ipsj.or.jp/en/computer/word/0027.html ]

2020-05-06 Thanks to NimShiko [https://medium.com/@elderiomeersky] for correction.