If a user submits a form, how does html send that form to a server database?

Question

If I coded up an html form, how do I store that form on my server?

Do I make it so, boom user types into form, user clicks submit button, then the html has a process where it sends the form data to a particular server, and after that it is the servers problem with how to store it?

If so, could I code the backend in C, and make it so the C just stores it in a notepad file?