Okay, kiddo! Have you ever seen a piece of paper towel? You know how it's usually white, right? Well, a white roll is basically a big roll of that same kind of paper, but it's used for different things.
Sometimes, people use white rolls to clean up messy spills, kind of like how you use a paper towel. But because it's a big roll, they cut off just the amount they need and don't have to waste a whole sheet of paper like you might sometimes do.
White rolls can also be used by artists to create art. If they're drawing with charcoal or pastels, they might use a white roll to smudge and blend the different colors together.
So, in summary, a white roll is a big roll of white paper that can be used for cleaning up spills or for artistic purposes. It's kind of like a giant paper towel!