The social networking site known for its 280-character limit on posts is Twitter. This platform was previously known as having a 140-character limit, but it was doubled in 2017 to allow users to express themselves more fully. Twitter is widely used for sharing news, engaging in discussions, and connecting with followers. By maintaining the character limit, Twitter encourages brevity and concise communication, which distinguishes it from other social media platforms. The site is also recognized for its real-time content and trending topics.