Why your hardware keeps disconnecting and how to fix it

Your computer is driving you crazy again.
The Wi-Fi keeps disconnecting or disappearing entirely, the mouse suddenly doesn't exist or stops responding. The keyboard starts typing whatever it feels like, regardless of which keys you're actually pressing.

It's infuriating, and I get complaints like these all the time.
So why does this happen? How can you fix these issues, and is it possible to prevent them altogether?
All of that — in the following article.

Why your hardware keeps disconnecting and how to fix it