Switch users : This is when you have more than one profile on your computer.. You might have your profile (Administrator). This is what comes up when you first turn your computer on, It usually has...
Log off will close all your programs. Switch user will keep them open.
See if the holes in the metal grid are blocked so that the flames can not come up.
login is to go in acount. logout is to get out of a account
It is log in on some websites, and log on with others.