Ruby has become increasingly popular for web development, leading to the creation of various frameworks designed for different needs, especially in building REST APIs. Roda is a minimalist framework known for its speed and efficiency, using a tree-based routing system that allows for lightweight and high-performance applications. Sinatra offers a slightly more complex but user-friendly experience compared to Roda, providing more built-in features at the cost of some performance. Padrino builds on top of Sinatra, blending its simplicity with the robust functionality of Ruby on Rails, making it suitable for medium-sized projects with its project generators and scaffolding. Ruby on Rails, known for its comprehensive feature set, is best suited for large, complex applications due to its extensive community and resources, despite being considered too heavy for simple APIs. When choosing a Ruby framework, considerations such as performance, ease of use, community support, and project size are crucial factors in selecting the appropriate tool for a project's specific requirements.