Anyone can create a misleading or downright false social media post. Those who see it may believe it—and share it—if it seems like it might be true and if it aligns with their pre-existing values and beliefs. For example, someone who already believes climate change is a hoax is likely to share posts that align with that belief, even if they are fabricated. The more something is shared and seen, the truer it can start to seem, due to what’s known as the mere exposure effect. Social media algorithms may further fuel the spread of disinformation, serving users increasingly polarizing or extreme content in order to keep them engaged.