Ruby on Rails can be used to build a variety of web applications, including:
E-commerce Platforms: Rails is often used to build online marketplaces due to its scalability and security features.
Social Networking Sites: The speed and ease of Rails development make it ideal for creating social networking platforms.
Content Management Systems: Rails can be used to develop robust and flexible CMS for various needs.
Streaming Sites: Rails can handle live streaming and video content, making it suitable for building video streaming sites.