When I run this command:

sudo systemsetup -getcomputersleep

I'm getting this:

Computer Sleep: after 55 minutes

And that corresponds to the setting in the "Energy Sever" Preference panel, the setting "Turn display off after".

So now I'm wondering what happens exactly after 55 minutes? Does the computer actually goes to sleep (i.e. all activity is stopped) or is it only switching off the screen?

The command line and Preference use wordings that for me means completely different things so I'm just wondering which one is right.