Social proof bias is closely related to conformity bias. It's the idea that people look to others' behavior to determine what is correct or appropriate in a given situation. This bias is based on the assumption that the majority of people must be doing something for a good reason. For example, you might be more likely to try a new restaurant if you see that it's crowded with people, even if you've never heard anything about the food quality. Social proof bias can be dangerous, though, because it can lead people to make bad decisions based on faulty information.