You're using your Windows XP, and suddenly your sister who's late for school comes running down the stairs, pulls your arm, and needs to print her homework. The fastest way to do that is to use a keyboard shortcut for switching users. Press the Windows logo key + L to quickly switch to the Welcome screen. Neat huh?

Fast User Switching is not available for members of a domain. Fast User Switching will not appear if it has not been turned on in User Accounts in Control Panel.