Multiple Users Logged Into Windows?

[Guest]

I have Windows XP Home Edition, and was logged in as the administrator. When
I shut the computer down it said other users were logged into Windows and if
I shut down they would lose their work. I told it to go ahead, but my
question is, how can more than one person be logged into the same computer at
the same time? And how did they get into my computer? The computer had been
online earlier in the day (broadband) but we unplug the modem and router when
we're not using the Internet. Only one other person has used that computer
today, and she used it under the administrator account. No other computer in
the house was turned on or plugged in today. Did someone hack into my
computer?

 

[Guest]

Dont worry about hacking. No one had hacked your computer. One of other users
have logged with their username (or you) then used fast user switch to change
Administrator. So it didnt log out so it says this.