TTY: Controlling terminal associated with the process.

RSS: Resident set size, the non-swapped physical memory that a task has used.

VSZ: Virtual memory usage of the entire process.

%MEM: Ratio of the process's resident set size to the physical memory on the machine.

%CPU: CPU time used divided by the time the process has been running.

USER: The effective user (the one whose access we are using).

You'll notice you're seeing a lot more fields now, no need to memorize them all, in a later course on advanced processes, we'll go over some of these again:

And finally the x lists all processes that don't have a TTY associated with it, these programs will show a ? in the TTY field, they are most common in daemon processes that launch as part of the system startup. The u shows more details about the processes. The a displays all processes running, including the ones being ran by other users.

If you are curious the difference between the styles is the amount of dashes you use and the flags. In my opinion the BSD style is more popular to use, so we're gonna go with that. If you look at the man page for ps you'll see that there are lots of command options you can pass, they will vary depending on what options you want to use - BSD, GNU or Unix. TTY: Controlling terminal associated with the process (we'll go in detail about this later).

This shows you a quick snapshot of the current processes: Go ahead and run the ps command to see a list of running processes: This PID is assigned in the order that processes are created. They are managed by the kernel and each process has an ID associated with it called the process ID (PID). Processes are the programs that are running on your machine.

Linux display processes