What is the command to view the details of currently logged-in users?

The command used to view the details of currently logged-in users is "w". This command provides a wealth of information about the users currently logged into the system, including their usernames, the terminal they are using, how long they have been idle, and what command they are currently running. It gives a snapshot of user activity on the system, making it useful for system administrators who need to monitor actively logged-in users and their activities.

In contrast, other commands serve different purposes. For example, "groups" displays the group memberships for a specified user or the current user if no user is specified, rather than listing currently logged-in users. The "id" command returns the user and group information for the specified user, providing details like user ID (UID) and group IDs (GIDs), but does not show information about all logged-in users. Lastly, "whoami" simply returns the username of the current user executing the command, providing no context about other users logged into the system. Thus, "w" is the most comprehensive tool for viewing logged-in users and their activities.