system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5:What exactly is happening when a program is "not responding" but continuously consumes large portions of CPU and memory?
gpt
In a graphical environment like windows, programs receive input like mouse clicks and keystrokes and they are required to respond to requests like redrawing the graphics in their window.  When a program starts failing to do that in a timely manner, the os deems it "not responding" and gives users options to wait or kill it.

Sometimes that happens because the program is calculating something complicated... but only when it's a shitty program.  Using threads and other techniques it's possible to have a program work on a big task without becoming non-responsive.

It can also just mean that the program has crashed, that is, gone into some kind of loop that it will never escape from.  There's no way for the operating system to tell the difference between those two cases, which is why it asks you.  (And there never will be.)