htop is the go-to interactive process monitor for Linux, macOS, and BSD. Where the classic top is cramped and keyboard-hostile, htop gives you scrollable process lists, per-core CPU meters, color-coded memory and swap gauges, and full mouse support. You can scroll horizontally to see complete command lines, search and filter processes, and kill or renice them with a keystroke instead of hunting for PIDs.
Launching it is just:
htopFrom there, F6 sorts, F4 filters, F9 sends signals, and F5 switches to a tree view showing parent-child process relationships. It's highly configurable: you can rearrange columns, change meters, and save your setup. Because it's been a standard for so long, it's available in virtually every package repository and is usually one of the first tools admins install on a fresh server. For quick, human-friendly insight into what's eating CPU or memory right now, htop remains hard to beat.