Electron is an open source framework, created by GitHub, that lets you develop desktop executables that bring together Node and Chrome to provide a full GUI experience. Electron has been used for several well-known projects, including developer tools such as Visual Studio Code, Atom, and Light Table. Basically, you can define the UI with HTML, CSS, and JS (or using React, as we'll be doing), but you can also use all of the packages and functions in Node, so you won't be limited to a sandboxed experience, being able to go beyond what you could do with just a browser.
You may also want to read about Progressive Web Apps (PWA) which are web apps that can be "installed" at your machine, very much like they were native apps. These apps are launched as any other app, and run in a common app window, without tabs or a URL bar as a browser...
