h left
j down (down arrow)
k up
l right

key notation : <>

ex :
  <Enter>
  <C-r> control r
  <M-Esc> meta (alt) escape

command : operator + amount + motion

ops :
  c change
  d delete
  y yank (copy)

motions :
  w start of next word
  e end of current word
  $ end of the line

special :
  o insert line below
  O insert line above
  G go to line
  dd delete line
  R replace (like insert button in other ides)
  r? replace char with ?
  /? search for ? in current file (<C-i> to jump fwd and <C-o> to backw)
  x delete char
  u undo command
  U undo line
  <C-r> redo
  p put text (last deletion or clipboard)
  P   "     "     "     "   before   "
  v start selecting

pressing num before motion repeats it
0 is start of line