Basic Movement and Editing Commands

C-x C-f Find file and load into buffer (Emacs prompts for filename)
C-x C-s Save the current buffer
C-x C-w Save the current buffer under a different name (Emacs prompts for the new name)
C-x C-c Quit Emacs, prompting if you have not saved any buffers
Arrow keys or C-f, C-b, C-n, C-p Right (forward), left (back), down (next), up (previous), respectively
C-k Delete from cursor to end of line
C-a Go to start of line
C-e Go to end of line
C-v Go down a page
M-v Go up a page
M-f Go to next word
M-b Go back one word
M-a Go to previous sentence
M-b Go to next sentence
C-x u Undo
C-g Abort the current command
C-l Redraw and center screen at cursor
M-< Go to start of buffer
M-> Go to end of buffer
C-d Delete next character
M-d Delete next word
M-| Execute shell command on region
Backspace Delete previous character