Three ideas nested like Russian dolls

Picture a set of Russian nesting dolls. The biggest doll is artificial intelligence. Inside it is machine learning. And inside machine learning are neural networks. Each doll is smaller and more specific than the one before.

  1. Artificial intelligenceAnything where a machine does something "smart": plays chess, translates, recognizes faces. That includes simple rule-based systems people wrote by hand: "if the customer typed the word 'refund,' send them to the refunds team."
  2. Machine learningHere, nobody writes the rules. The machine is shown thousands of examples and finds the pattern on its own. Your email spam filter learned exactly this way: from mountains of messages people marked as junk.
  3. Neural networkThe most powerful kind of machine learning. Millions of simple connections that adjust themselves to the examples. Neural networks are what draw pictures, voice text, and hold conversations.

How exactly a neural network learns from examples is covered in detail in what is a neural network in plain English