How does 'who' differ from 'w'?

The who and w commands are both used to display information about users currently logged into a Unix-like system, but they provide different levels of detail and context. Here’s a breakdown of their differences:

who Command

• Purpose: Displays a list of users currently logged into the system.
• Output: Shows basic information such as the username, terminal (TTY), login time, and the originating IP address or hostname.
• Use Case: Useful for quickly checking who is logged in without additional details about their activity.

Example Output:

labex    pts/0        2023-10-01 10:00 (192.168.1.5)

w Command

• Purpose: Provides a more detailed view of logged-in users, including their current activity.
• Output: Displays the username, terminal, login time, idle time, JCPU (time used by all processes), PCPU (time used by the current process), and the command currently being executed by each user.
• Use Case: Useful for monitoring user activity and system load, as it shows what users are doing in real-time.

Example Output:

 10:05:01 up  1:00,  1 user,  load average: 0.00, 0.01, 0.05
USER     TTY      FROM             LOGIN@   IDLE   JCPU   PCPU WHAT
labex    pts/0    192.168.1.5      10:00    1.00s  0.01s  0.00s w

Summary of Differences

• Detail Level: who provides basic login information, while w includes detailed activity and system load.
• Usefulness: Use who for a quick check of logged-in users and w for monitoring user activity and system performance.

If you have any further questions or need clarification on these commands, feel free to ask!