Skinners experiments and findings were actually based on Thorndike’s conclusions, but skinner believed that the animals used their minds. Skinner used rats and doves in between other animals to conduct his experiments. He would place a rat inside a box and give him rewards whenever he got closer to its goal and whenever he would go to farther he would get a punishment. So the rat got to learn what he had to do to get the reward and step by step he got to its goal. With the pigeon, there were differnet cases, but it was relatively the same.
What reinforcement does is that it increases behavior and what ounishment does is to decreasse behavior. What negative means is when you take something away as a reinforcement or as a punishment and positive means that you give something as a punishment or reinforcement.