I think he's asking about how to do keyboard formatting on SF, which can be done with the kbd tag. For example:
<kbd>Ctrl</kbd>+<kbd>E</kbd>
Should render as:
Ctrl+E
Well, I see it doesn't work here on meta.SF, which might be a glitch. This question on meta.SO refers to the kbd tag being disabled on meta (I think people were drawing pictures of castles with it), so maybe it's disabled on all the meta sites.