Okay, so imagine you're playing hide-and-seek and you're trying to find your friend. But instead of your friend hiding in a spot where you can see them, they've hidden somewhere you can't see. That place where you can't see them is like the "cloud of unknowing." It's a spot that you don't know about, and you can't really find because it's not visible to you.
The "cloud of unknowing" is actually a kind of spiritual idea that some people talk about. It's when you're not sure about something, and you don't know what the answer is. It's like there's a "cloud" that's hiding the truth from you, just like your friend was hiding from you when you were playing hide-and-seek.
Sometimes this cloud can be about religious ideas or feelings, and people might use it to talk about how they're not sure what they believe. Other times it can be about more practical things, like not understanding how a computer program works. It's like there's a "cloud" in front of their understanding, and they can't see what's going on behind it.
So just like when you're playing hide-and-seek and you have to keep looking around until you find your friend, sometimes when you're dealing with the cloud of unknowing, you have to keep searching for answers until you finally understand what's going on.