Bootstrap is a free and open-source CSS framework directed at responsive, mobile-first front-end web development. It contains CSS and JavaScript-based design templates for typography, forms, buttons, navigation, and other interface components.
Emotion is a library designed for writing CSS styles with JavaScript.
MUI(formerly Material UI) is a simple and customisable component library to build faster, beautiful, and more accessible React applications.
Next.js is a React framework for developing single page Javascript applications.