It represents JavaScript code intended for execution outside of a web browser, commonly on a server. A widespread application involves creating dynamic web content and handling backend logic. For example, one might use this technology to build an API endpoint that retrieves data from a database and delivers it to a client-side application.
Its significance lies in enabling full-stack JavaScript development, allowing developers to use a single language for both frontend and backend development. This promotes code reusability, streamlines workflows, and simplifies team collaboration. Historically, this approach emerged to address the limitations of client-side JavaScript, providing a powerful alternative for server-side programming.