React.js and Angular are two popular open-source JavaScript frameworks used for front-end development.

React.js is a JavaScript library created by Facebook for building user interfaces. It uses a component-based structure, which allows developers to break down complex user interfaces into smaller, more manageable pieces. React.js offers more flexibility than traditional Model-View-Controller (MVC) frameworks, allowing developers to create custom components for their projects.

Angular is a full-featured MVC framework from Google. It allows developers to create single page web applications by combining data from a Model layer with components from a View layer. Angular's component-based architechture insulates developers from many of the complexities of modern web programming, allowing them to easily create, update and delete objects.

Both React.js and Angular offer different approaches to web development, and thus are suitable for different use cases. For some projects, React.js might be a better choice due to its flexibility, while Angular could be a better choice in other cases due to its robust architecture. Ultimately, the decision on which framework to use should come down to the project at hand and developers' preferences.

For more information, see the following link: https://developer.telerik.com/topics/web-development/angular-vs-react-which-framework-should-you-choose-your-next-project/