So I've seen things like WordPress and FCKEditor, and basically a bunch of stuff that uses external code that I can't see or edit. Whenever I ask about editing and saving the content of a page in real time I just get referenced to an API or I get handed code that only changes the page until it's reloaded.

What I want to know is how do I code it myself? I want to add real time content editing to a page without the use of someone else's code. I've checked out code for various forums and wikipedia and whatnot, and all of it references code I don't have access to.

Is this a thing? Can I edit a page in real time? I thought of writing the edited text to a file on the server, and then when they click save, reading it back into the code to the section they were editing, but I don't know how to do that or if it's even possible.

As a side note, I'm very new to html, but not new to coding.

EDIT: The structure can be very much like Wikipedia, it doesn't have to be real time, it just has to work