Though I am an Angular JS type of person, I regularly follow other JavaScript frameworks to keep up with the rest of the world. React, along with the Flux design pattern, is a relatively popular alternative to the Angular ecosystem. However, React+Flux is extremely different from other frameworks-- for starters, React isn't actually a full JavaScript framework by itself, and Flux isn't actually a thing: it's a type of architecture. Tero Parviainen wrote an amazing introduction to the Redux+React ecosystem with an overview of how not only the two libraries themselves work, but conceptually how they fit together and why the Flux architecture and immutability makes sense in a web application.