Opening an app

When you open an app, the computer loads it from storage into RAM. Storage is where everything lives when it's not in use. RAM is the fast, temporary workspace for whatever is active right now.

The CPU then runs the app's instructions, one step at a time, handling the logic and deciding what happens next.

If the app needs to draw anything on screen, the CPU hands that work to the GPU. The GPU is built for images: it splits the picture into thousands of tiny pieces and works on all of them at the same time.