Command mode ESC

dd       delete
u        undelete
y        yank (copy to buffer)
p/P      p before cursor/P after cursor

Ctl-g    show current line number
shft-G   end of file
n shft-G   move to line n

/stuff/   search
n   repeat in same direction
N   repeat in opposite direction
/return  repeat seach forward
?return  repeat seach backward

"dyy  Yank current line to buffer d
"a7yy Yank next 7 lines to buffer a
or
:1,7ya a  Yank [ya] lines 1,7 to buffer a
:1,7ya b  Yank [ya] lines 1,7 to buffer b

:5 pu b   Put [pu] buffer b after line 5

"dP   Put the content of buffer d before cursor
"ap   Put the contents of buffer a after cursor

:1,4 w! file2  Write lines 1,4 to file2
:1,3

:set nu     Display line numbers
:set nonum  Turns off display

:e <filename> Edit a file in a new buffer

vim
:split
:split <filename>
:sp <filename>
:split new

ctl-w   To move between windows
ctl-w+
ctl-w-  To change size
ctl+wv  Split windows vertically
ctl-wq  Close window

:only       To view only 1 window

vim dictionary - put the following command in ~/.vimrc

set dictionary+=/usr/share/dict/words
set thesaurus+=/usr/share/dict/words

Now, after you type a word <ctl-x><ctl-k><ctl-n> and to
go back in the listing <ctl-p>

butter<ctl-x><ctl-k><ctl-n>