Vue JS is a progressive framework for building user interfaces. It uses a component-driven approach and features like reactivity and computed properties that make it possible to build desktop, mobile, and web applications. Some key features include reactive data binding, conditional rendering, mixins, slots for content distribution, and Vuex for global state management between components. Asynchronous and dynamic components add flexibility. Vue shares similarities with React in using virtual DOM and components but differs in file structure and size.