Facebook, Instagram, TikTok, and YouTube are all social media platforms, but they differ in their primary features and target audience. Facebook is a general social networking site that allows users to connect with friends and family, share content, and join groups based on shared interests. Facebook has a wide range of users, from teenagers to seniors. Instagram is a photo and video sharing app that focuses on visual content. Users can share photos and videos with their followers, and can also follow other users and see their content in their feed. Instagram's main demographic is younger adults, with a large portion of users in the 18-29 age range. TikTok is a social media app that allows users to create and share short videos set to music. The app is known for its viral challenges and trends, and has a large user base of younger users. TikTok is popular among teenagers and young adults, with a significant portion of its users aged 16-24. YouTube is a video sharing platform that allows users to upload, share, and view videos on a variety of topics. The platform has a wide range of content, from music videos to tutorials, and is popular among all age groups. YouTube also offers a monetization program for creators, allowing them to earn money from their content. In summary, while all of these platforms are social media sites, they differ in their primary features and target audience. Facebook is a general social networking site, Instagram is focused on visual content, TikTok is centered around short videos, and YouTube is a video sharing platform with a wide range of content.