Social media marketing is when businesses or people use websites and apps like Facebook, Twitter, Instagram, and YouTube to promote themselves and their products or services. It works by businesses creating posts with interesting content and information about the company and its products or services. Those posts show up in people's feeds, and if it's good enough, people will click your post and find out more about you. The goal is to get people to like and follow your page, and hopefully if you keep providing interesting content, people will remember you and visit your website or buy your products.