Zend Framework (ZF) is an open source, object-oriented web application framework implemented in PHP 5 and licensed under the New BSD License. Developed by Zend
License: Open Source
Zend Framework is a robust, enterprise-level PHP framework known for its flexibility and customizability, making it suitable for large applications. Ruby on Rails, on the other hand, emphasizes rapid development and ease of use, favored by startups for its convention-over-configuration approach.