Okay kiddo, so you know that everything in the world is made up of tiny little pieces called atoms, right? And atoms have even tinier pieces inside of them called protons and neutrons. Well, a diproton is when two little protons get stuck together!
Now, this might sound like a good thing at first, because two is better than one, right? But actually, diprotons aren't very stable. They don't stick together for very long before breaking apart. Scientists have actually never been able to observe a diproton in real life, because they break apart so quickly.
But don't worry, this is all just science stuff that grown-ups are trying to figure out. For now, all you need to know is that a diproton is when two little protons come together, but it doesn't last very long.