Task Manager

In short: A system tool (on Windows, the “Task Manager”) that shows running processes and monitors their resource usage (CPU, RAM, network).

In more detail: Lets you specifically terminate hung or resource-hogging programs, without having to restart the entire system. Comparable tools on other systems: Activity Monitor on macOS, or top/htop on Linux.

In Depth

The Windows Task Manager (opened via Ctrl+Shift+Esc or Ctrl+Alt+Del) shows several tabs: running processes with their current CPU, RAM, disk and network load, startup programs, and details like process ID (PID) and priority. Right-clicking a process lets you end it (“End task”), change its priority, or bind it specifically to a particular CPU core (“Set affinity”).

The Linux equivalent, top, shows the same information in text form in the terminal, updated live:

top - 14:32:07 up 3 days,  2:14,  1 user,  load average: 0.42, 0.38, 0.35
Tasks: 218 total,   1 running, 217 sleeping
%Cpu(s):  3.2 us,  1.1 sy,  0.0 ni, 95.4 id
MiB Mem :  16384.0 total,   8213.5 free
  PID USER      PR  NI    VIRT    RES  %CPU  %MEM  COMMAND
 1203 mzell     20   0  892400  45200   2.3   0.3  node

htop is a more comfortable, interactive evolution of top, with colour display, mouse support, and easier termination of processes at the press of a key — not pre-installed on most Linux distributions, but quickly added via the package manager (apt install htop, dnf install htop, etc.). All three tools solve the same basic problem: giving a quick overview of which process is currently eating up resources, and the ability to step in directly.

Process vs. service

An important detail for troubleshooting: the Task Manager shows both normal, user-started applications and background services (on Windows, via the “Services” tab, all running in the background as svchost.exe processes with different service IDs). A single visible process can host several services at once, which makes figuring out “which service is causing this load” harder without a closer look — but the Task Manager lets you specifically search for the responsible service within an svchost process.

When a process is really “hung”

Not every process with high CPU usage is a problem — some programs (e.g. video conversion, compiling) deliberately use a lot of computing power for a limited time. A real “hang” usually shows up as “Not Responding” in the Task Manager (Windows explicitly marks this), combined with permanently constant instead of fluctuating resource usage. Before forcibly terminating a process, it’s therefore worth briefly checking whether the load plausibly matches the current activity, to avoid accidentally aborting an actually working, just computationally intensive operation.

See also: Service