ELI5: Explain Like I'm 5

IRQL (Windows)

IRQL (Interrupt Request Level) is a big word for how important things are in a computer. Imagine you’re playing with blocks and it’s time for dinner. You’ve built a tall tower, but your mom says you can’t leave it until you put away your toys. Now imagine the blocks are all the different things that a computer needs to do, like running a program or saving a file. Your mom is like the operating system of the computer, making sure everything works smoothly.

Just like your mom, the operating system of your computer has to manage all the different things it needs to do. But sometimes, something really important comes up and the computer has to focus all its attention on that one thing. This is where IRQL comes in. It’s like your mom saying, “Put away your blocks, it’s time for dinner now!”

IRQL has eight levels, from 0 to 7, with 0 being the most important. When something really important happens on your computer, like a program crashes or a hardware device has a problem, the operating system jumps to a higher IRQL level to deal with it right away. This means other things that aren’t as important have to wait until the important thing is taken care of.

Think of it like your mom saying, “Dinner’s ready!” That means your blocks have to wait until after you eat to be put away. Once the important thing is done, the computer goes back to a lower IRQL level and can start working on the other things again.

In summary, IRQL is a way for the operating system of a computer to manage all the different things it needs to do, and to prioritize important tasks over less important ones. It’s like your mom telling you what’s most important to do first.