A Full Stack Developer is a software professional who can work on both the frontend (client-side) and the backend (server-side) of a project. Full Stack Developers are knowledgeable about all levels of the technology stack that go into creating a software product. There are two prominent all-encompassing technological stacks in the Javascript world: the MERN stack (MongoDB, ExpressJs, ReactJs, NodeJs) and the MEAN stack (MongoDB, ExpressJs, AngularJs, NodeJs).