Is knowledge also a belief?

Thinking something is true is not a similar process as understanding something to be true. Perhaps in your mind it is though? Perhaps in my mind it is not. How can we know? Interesting thought there.

On Animals and very young children - how do you know they don’t? What if they do? Perhaps it is a matter of a well enough working complex brain to distinguish, but perhaps they just can’t communicate it either. Is this whole matter only justifiable for my brain? Does everyone need to parse knowledge, belief, opinion and truth their own way or can we get a reasonable generalization, and if so why not the one I am proposing in its infancy?