Unsupervised training is the deep learning equal of context clues. It sees people talking about cats, sees an image guesses cat. Sees similar images + similar words, eventually builds a cat type prototype.

What I'm talking about is a child can see a photo of an unknown animal, I can show that child a cartoon elephant (which is the original animal). I then ask what the original animal is, the child likely responds correctly.

Reprocessing of already learned data as the scheme of the world changes based on new information.