Hkey_users
The Windows registry subtree that contains information about the currently logged-on user is the HKEY_CURRENT_USER (HKCU) hive. This hive includes user-specific settings and configurations, such as preferences, environment variables, and application settings. It is dynamically linked to the HKEY_USERS subtree, which holds profiles for all users on the system, with HKCU representing the active user's profile.
They get priority for the music stations in last.fm, and they can see who (among registered and logged in users) visits their profile page.
It's Mandatory User Profile: a roaming profile that users cannot change.
Only one user at a time can be logged into Windows 2000 Professional. Any number of users can be logged into a Terminal Server; it isn't unusual for a large business to have 100,000 users logged into one server.
No, many users cannot be logged in the same time. Only server OS can do that. There are some "hacks" which you can do with your Xp to allow many terminal sessions in the same time. Which includes replacing some dlls with ones from Windows server 2003, and editing the registry. If you mean many users access to shared folders or printers, then the answer is yes. You can do that without any "hacks".
Instant Messenger is a program that allows two users to communicate simultaneously. You can download a program that allows you to do this on your computer.
users
who command gives the list of users who have currently logged in......
Press Control, Alt, Delete. Alternatively, right click the taskbar and choose "Task Manager" from the context menu and you'll see the Task Manager. Choose the "Users" tab. It will list users currently logged in!
A Roaming profile is where setting established by a user at one computer are stored in a file on a file server on the network and shared with all computers in the workgroup, When a user moves from one computer to the next in the workgroup the roaming profile follows the user so that he or she does not have to redo settings at each computer. A Mandatory profile is a roaming profile that applies to all users in a user group, and individual users cannot change that profile. It is used in situations were users perform only specific job-related task.
Authorization code is generated for those Facebook users who have integrated their profile with their personal cell number as a security. Whenever the profile is logged in, Facebook instantly sends the authorization code to the user cell phone to access the profile. This is a strict security, you cannot access anyone's' profile that easily.
Non-logged in users can view nearly all the same content as logged in users. So they can view your account, boards, and pins, but are unable to see your followers and who you're following.