I have been reading an article on AlphaGo and one sentence confused me a little bit, because I'm not sure what it exactly means. The article says:
AlphaGo Zero only uses the black and white stones from the Go board as its input, whereas previous versions of AlphaGo included a small number of hand-engineered features.
What exactly is the input to AlphaGo's neural network? What do they mean by "just white and black stones as input"? What kind of information is the neural network using? The position of the stones?