Answer 1

Do you mean form method in html which is POST or GET?
That is the request method that it will use when it sends the data to the target url.

In PHP we use $_POST and $_GET to catch the incoming data that is coming from the html form or any http request.

I have similar answer here
https://www.sololearn.com/Discuss/1042644/what-happen-to-the-information-after-submitted-html