The document discusses prohibitions and obligations. Prohibitions are things that are forbidden and express prohibitions using phrases like "you can't", "you're not allowed to", or "you're not permitted to". Obligations are things that are necessary and use phrases like "you have to", "you need to", or "you must". A few examples provided are that customers are not allowed to enter, you need to lock your car, you can't smoke in closed areas, and you have to be over thirteen.