Windows XP has a Fast User Switching mode of operation that allows more than one user to be logged onto the computer at the same time. This is accomplished by creating a separate session for each user that logs on, however only one of these sessions is allowed to be active at any one time, whether that is sitting at the machine (termed the console) or via a remote connection. You can switch from one user session to another by using the hot key combination of WinKey+L (the Windows logo key and the ????L?????? key together) or by using the Switch User button on the log off dialog. Both of these methods disconnect the current session (rather than ending it) and present the welcome screen. At this point logging in as another user will either connect you with the previously disconnected session for that user or create a new session for that user. This process can be used to create multiple sessions and to switch between them.
||Free to try
Windows NT 4