The top command, which means table of processes, is similar in nature to Windows Task Manager. You will find a wide variety of Linux distributions that support the top command. The top command is essentially used to derive the system's CPU and memory utilization. The output is structured by creating a list of running processes selected by user-specified criteria; the output is in real time. The PID for each process is listed in the first column. Let's fire it up:
[philip@localhost ~]$ top
top - 12:50:44 up 5 days, 11:44, 2 users, load average: 0.01, 0.02, 0.05
Tasks: 165 total, 1 running, 164 sleeping, 0 stopped, 0 zombie
%Cpu(s): 12.1 us, 1.4 sy, 0.0 ni, 86.1 id, 0.0 wa, 0.0 hi, 0.4 si, 0.0 st
KiB Mem : 999696 total, 95804 free, 633636 used, 270256 buff/cache
KiB Swap: 2097148 total, 1852900 free...
