Interactive process viewer for real-time Linux monitoring and quick interventions. 24.03.2026 | reading time: 3 min Want to know which process is chewing CPU or leaking memory right now? htop is an interactive, ncurses-based process viewer that lets a user inspect, sort and act on processes in real time, making troubleshooting immediate and visual. Live demo Try this on a test system: start htop and observe processes, then filter a PID and focus on a single process; example session shown below demonstrates typical output and how to monitor a specific PID: ``` $ htop PID USER PRI NI VIRT RES SHR S CPU% MEM% TIME+ Command 1234 bob 20 0 150M 12M 8M S 0.0 0.2 0:00.12 sleep 100 2345 root 20 0 1.2G 100M 20M S 3.2 1.3 1:23.45 nginx: worker ``` To view only PID 2345 use `htop -p 2345` or to see processes of one user use `htop -u username`. Power controls Once inside htop a few keys change everything: press F6 to change sort column, F5 to toggle tree view, F3 to search, F9 to send a signal (kill), and F2 to open setup; run `sudo htop` to see system-wide processes that a regular user cannot, and use `htop -p` or `htop -u` from the shell to pre-filter before the UI appears. When it helps most Reach for htop when you need a quick live answer: find runaway processes by CPU or memory, inspect per-thread usage, trace spikes over seconds, or send a SIGTERM/SIGKILL without composing a separate `kill` command; it is especially handy inside a terminal multiplexer like tmux on production boxes. Other viewers htop is interactive and colorful, but `top` is universally available, `ps` is scriptable and perfect for snapshots, and `glances` gives a broader dashboard with plugins; choose the tool that fits whether you need an interactive drill-down, a one-off report, or integration in a monitoring script. Finish line Mastering htop makes everyday troubleshooting faster and more confident; keep practicing on lab systems and consider formalizing knowledge with certifications like CompTIA Linux+ or LPIC-1, and use bitsandbytes.academy for intensive exam preparation. Join Bits & Bytes Academy First class LINUX exam preparation. utilities processes troubleshooting
