This fallacy assumes that something is true or good simply because many people believe it or do it. It plays on the desire to be accepted and liked, and often uses phrases like "everyone knows," "everybody's doing it," or "it's the popular thing to do."
Example: "If you really want to fit in with the cool kids, you need to start wearing this brand of shoes."
While the appeal to popularity can be persuasive, it's important to recognize that it doesn't necessarily provide a logical or valid argument. It's crucial to evaluate the merits of a course of action based on evidence and reasoning, not just on whether it will make you popular.