Earnstack stands for Mongo DB, Express JS, Angular, and Node JS. It is a set of these technologies used to develop each end of a web application. Earnstack stands for Mongo DB, Express JS, Angular, and Node JS. It is a set of these technologies used to develop each end of a web application. Angular handles the implementation of the User Interface (UI), and when the UI needs data, it sends a request to the server, asking it to get the required information from MongoDB.