The JAMstack is a term popularized by React community, referring to "Javascript", "APIs" and "Markup". It covers static content frameworks like Next.js, Gatsby, and 11ty; deploy platforms for hosting applications; cloud functions or serverless services that handle API requests; headless CMSes for managing content; and advanced features such as authentication and databases. The JAMstack gained popularity due to its ability to provide both server-side rendered HTML and interactive React components, offering the best of both worlds. Mux is a video API for the JAMstack that focuses on handling backend or "serverless" part of the video stack while allowing developers to control every aspect of user experience.