EMACS

HELP:
C-h m	curent mode info
C-h k	key bind info
C-h a	search function
MAIN:
C-x C-c	exit
C-/	undo
[space] C-/	redo
C-x C-b	buffer list
C-g | Esc Esc Esc	keyboard quit
C-x b	switch between buffers
C-x C-w	save buffer as
C-x C-f	open file
C-u [nr] [arg]	repeat argument [nr] times, default 4 times
SEARCH:
C-s	search forward
C-r	search backward
M-%	find and repleace
BUFFERS:
C-x C-s	save all buffers
C-x s	save current buffer
C-x k	kill buffer
C-x C-b	show buffer menu
BUFFER MENU:
d	kill buffer
s	save buffer
x	perform previously requested deletions and saves
u	undo save and kill
%	read only flag
*	modify flag
q	quit buffer menu
o	open buffer in another window
WINDOWS:
C-x 2	horizontal window
C-x 3	vertical window
C-x 0	remove current window
C-x 1	remove all other windows
C-x o	change window
C-x ^	taller window
C-x }	wider window
EDIT:
C-[space]	select
C-[space] [space]	unselect
M-w	copy the previously selected
C-w	cut the previously selected
C-y	paste
C-a C-k	delete line
C-k	delete from cursor to the end of line
C-h b	help key bindings
M-;	comment/uncomment
M-g g	go to line
C-x r t [string]	insert vertical column
C-x k	kill region
Alt ;	insert comment
C-x r t	insert character at every match line
C-x r k	delete first rectangle at match line(match upto next line field to delete)
INDENT:
C-u [num | -num] C-x [tab]	indent previous selected region [num] of lines, minus means indent left
OTHER MODE:
M-x dired	file manager mode
M-x python-mode	python mode