What is emacs pinky?

Some articles on emacs pinky, emacs, pinky:

GNU Emacs - Using Emacs - Emacs Pinky
... Many heavy Emacs users have experienced repetitive strain injury pain in their pinky fingers, dubbed the Emacs pinky, because of Emacs' strong dependence on Control and Meta keys, and in particular ... Although not limited to Emacs, many users transpose the left Control key and the left Caps-lock key ... Viper-mode, a feature built into Emacs that allows the use of the vi keys for basic text editing and the Emacs keys for more advanced features ...