Taken from: https://stackoverflow.com/a/7411851/12158779
In normal mode:
a: append
b: beginning (of current or previous word)
c: change
d: delete
e: end (of current word)
f: find (next given character on current line)
g: go (used as "leader" for many commands)
h: left (only makes sense on the keyboard used by vi's author, same for jkl)
i: insert
j: down
k: up
l: right
m: mark
n: next (occurrence of last search)
o: open (new line below current line)
p: put (paste)
q: quote? (record a macro in given register)
r: replace
s: substitute
t: toward (next given character on current line)
u: undo
v: (enter) visual mode
w: (next) word
x: x-out (delete a single character)
y: yank
z: fold (it's visual, it looks like a folded sheet of paper)