Preemption (computing)

Preemption is like when you're playing with a toy and your friend comes along and wants to play with it too, so your mom comes and takes the toy away from you so your friend can have a turn.

In the computer world, preemption happens when one program is using the computer's resources (like CPU or memory) and another program wants to use them too. The computer then stops the first program in the middle of what it's doing (just like your mom taking away your toy) so the other program can have a turn.

This happens really quickly, so you might not even notice it. It's like if you were playing a game on your tablet, but then your mom calls you for dinner, so you have to pause the game and come back to it later.

Preemption is important because it helps make sure that all the programs on the computer get a fair chance to use the resources they need. Just like how your mom wants you and your friend to share your toys, the computer wants all the programs to share its resources. And preemption helps make sure that happens.