Pre-emptive multitasking

Imagine you have a bunch of toys that you want to play with, but you can only play with one toy at a time. Pre-emptive multitasking is like having a grown-up who picks one toy for you to play with for a little bit, and then when it's time to switch toys, they take the toy away and give you a different toy to play with.

This grown-up is like the computer in your tablet or phone that decides which app or program gets to use the toy (the processor) to do its work. Pre-emptive multitasking means that the computer decides when each app or program gets to use the toy, and it can take it away if the app or program is doing too much or taking too long to finish.

This helps keep your tablet or phone running smoothly, even if you have lots of apps or programs open at the same time. It's like having a grown-up to keep things organized and make sure everyone gets a turn with the toys without fighting or causing a big mess.