What command do you use to check the current user logged in?

The command used to check the current user logged into a Linux system is "whoami." When you execute this command in the terminal, it outputs the username of the user currently logged into the session. This command is especially useful in scenarios where you might have switched users, such as using the "su" command, and you need to confirm which user context you are operating in.

The other options, while intuitive, do not exist as valid commands in standard Linux environments. "currentuser," "showuser," and "loguser" are not recognized commands, and attempting to use them will result in an error, indicating that the command is not found. Thus, "whoami" is the only correct and functional command for retrieving the current logged-in user's name.