React and Angular are two popular JavaScript frameworks used in modern frontend development, providing pre-built functionality and a framework for building responsive and interactive user interfaces. While they share similarities, React is a smaller library with a simpler architecture, focusing on view-side components, whereas Angular is a full-fledged framework offering a more comprehensive solution with MVC architecture, opinionated code structure, and robust tools for building complex applications. Both frameworks have their strengths and weaknesses, including flexibility, learning curve, ecosystem support, and performance, making it essential to consider project requirements, developer expertise, and specific needs when choosing between React and Angular for a new or existing project.