Vim Registers
"manpage" -> :help registers
view current register values -> :registers
change three words and put the previous three words into register c
"cc3w
Append the current line to register a
"Ayy
Blackhole register
leave my unnamed register alone!
"_ e.g. delete current line "_dd
record macro then use it again
qq -> do whatever -> q
run macro :normal @q
previous command register
":
after running a substitution one can repeat it using :@: