Task Manager is a built-in Windows tool that lists running applications and background processes together with their CPU, memory, disk, network and GPU use. Open it with Ctrl+Shift+Esc. macOS has Activity Monitor and Linux has tools such as top and htop.
Why it matters
It is the first place to look when a computer feels slow or an app has stopped responding. You can see which process uses the most memory, end a hung program, check performance graphs and disable programs that launch at startup. It also shows details such as process IDs and which user runs each process.
Example
If a browser freezes, open Task Manager, sort by Memory, select the unresponsive entry and click End task. In the Startup apps tab, you can see each entry's startup impact and disable heavy ones. A process called System using constant high disk may indicate a failing drive or heavy indexing.
Common mistakes
- Ending unknown system processes such as
csrss.exeorwinlogon.exe, which can crash Windows. - Assuming high memory usage is always bad; unused RAM is wasted, and the system caches freely.
- Trusting a process name alone to decide it is safe or malicious.
Related
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