Line numbers

Show/hide line numbers

:set number/nonumber

Cut/Copy/Paste

Keys

d: delete (cut)
y: yank (copy)
p/P: paste (after/before)

Split window

Ctrl+w s

Filesystem Explorer

:Explore

Sessions

Save a session

:mksession mysessionfile

Open a session

:source mysessionfile

Tabs

Open files in tabs:

vim -p file1 file2 file3

Open new file in tab:

:tabnew filename

Next/Previous tab:

:tabn/tabp