:e file – edit a file in a new buffer

:bnext or :bn – go to the next buffer

:bprev or :bp – go to the previous buffer

:bd – delete a buffer (close a file)

:ls – list all open buffers

:sp file – open a file in a new buffer and split window

:vsp file – open a file in a new buffer and vertically split window

Ctrl + ws – split window

Ctrl + ww – switch windows

Ctrl + wq – quit a window

Ctrl + wv – split window vertically

Ctrl + wh – move cursor to the left window (vertical split)

Ctrl + wl – move cursor to the right window (vertical split)

Ctrl + wj – move cursor to the window below (horizontal split)

Ctrl + wk – move cursor to the window above (horizontal split)

:execute 'normal "ayiw' | echo @a