none of them are robots, the man in black is a regular customer of the theme park. Most of the others are hosts. Did you ever see the film with Yul Brynner? In that they were robots in this they are genetically engineered synthetic people who are continually recycled and repaired they are programmable and have command input facilities. They cannot harm the guests but the guests can do what they like. The "Hosts" are not merely automaton, they are in fact thinking feeling entities that feel pain etc but to them it's like groundhog day, they relive certain themes over and over.