Random Access Memory (RAM)

Think of RAM as your desk.
Everything you're actively working on is spread out on it. Open tabs, running apps, the video you're watching. Fast to reach, always right there.

But when you leave and clear the desk, it's gone.

RAM is fast because it has to be. The processor is pulling from it billions of times a second. It only holds what's needed right now. Turn the computer off and it starts fresh.