I have recently used some software, which come as a regular setup file, where you install your software, and then when you run it, opens the browser, uses the localhost with some specific port number to connect to the software, and runs it from there. I find it quite useful and interesting. But I even don't know whether this kind of software and programming methodology have a name or not. Therefore, I would like to learn which programming languages, APIs, and frameworks are specifically designed for this purpose? One example to this is Metasploit. You can download its setup file, and install it casually like any other software, then when everything finishes, and you want to use the software. It will open the browser and connect to, http://localhost:3790/ where Metasploit will load and start.