The "query user" command is a useful tool in the Windows environment for system administrators who need to manage and monitor user sessions on a remote or local computer. This command provides detailed information about user sessions, including session names, user names, session IDs, states, idle times, and logon times. Understanding how to use the "query user" command can help administrators troubleshoot issues, manage resources, and ensure the security of the system.

Examples:

1. Basic Usage: To display information about all users who are currently logged on to the system, open the Command Prompt and type:

   query user

   This command will return a list of all active user sessions on the computer, similar to the following output:

   USERNAME              SESSIONNAME        ID  STATE   IDLE TIME  LOGON TIME
   johndoe               console             1  Active      none   10/10/2023 09:00 AM
   janedoe               rdp-tcp#1           2  Active      00:10   10/10/2023 09:15 AM

2. Query a Specific User: To query information about a specific user, you can specify the username as an argument. For example:

   query user johndoe

   This command will return information only about the user "johndoe".

3. Query User on a Remote Computer: To query user sessions on a remote computer, use the /server parameter followed by the name of the remote computer:

   query user /server:RemotePCName

   Replace RemotePCName with the actual name of the remote computer. This will display the user sessions on the specified remote machine.

4. Using PowerShell: While the query user command is a CMD utility, you can also achieve similar results using PowerShell. For example, to get the list of users logged into a remote computer, you can use:

   Get-WmiObject -Class Win32_LogonSession | 
   ForEach-Object { 
      $session = $_ 
      Get-WmiObject -Class Win32_LoggedOnUser | 
      Where-Object { $_.Dependent -eq $session.__PATH } | 
      Select-Object @{Name="UserName";Expression={$_.Antecedent -replace '.*Domain="([^"]+)",Name="([^"]+)".*','$1\$2'}}, 
                    @{Name="LogonId";Expression={$session.LogonId}}, 
                    @{Name="LogonType";Expression={$session.LogonType}} 
   }

   This PowerShell script will provide detailed information about the users logged into the system.