To spot an AI in the wild, it’s important to know the difference between machine learning algorithms (what we’re calling AI in this book) and traditional (what programmers call rules-based) programs. If you’ve ever done basic programming, or even used HTML to design a website, you’ve used a rules-based program. You create a list of commands, or rules, in a language the computer can understand, and the computer does exactly what you say. To solve a problem with a rules-based program, you have to know every step required to complete the program’s task and how to describe each one of those steps.

But a machine learning algorithm figures out the rules for itself via trial and error, gauging its success on goals the programmer has specified. The goal could be a list of examples to imitate, a game score to increase, or anything else. As the AI tries to reach this goal, it can discover rules and correlations that the programmer didn’t even know existed. Programming an AI is almost more like teaching a child than programming a computer.