Emacs

"You'll also see something like “(See ‘Extended’)” from time to time. We've listed the possible default keybindings for a function in its entry in the “Additional Features Manual,” so check there, too. Note that there are two different key binding maps in common use in the LyX community: the “CUA” style which is the default and familiar to those coming from the PC world, and the “emacs” style, which is common with those who “grew up” on Unix systems and use the Emacs editor. Unless specifically noted, the keybindings in the documentation are from the default CUA map. If you like Emacs, you should be smart enough to read the documentation and figure out the bindings on your own."

Taken from the LyX intro.lyx