Rename File in Emacs

First impression people have is that Emacs is an editor. So in an editor one should just save as to different name/path. ¹

But save as is different from renaming a file. save as creates a copy of the file with a different name/path. So one has two files with old and new paths.

But rename leaves just one file at thenew path.

Older versions of Emacs (< Emacs 26) did not have this functionality built-in So either one had to use dired or people wrote their own functions.

But now (rather from emacs 26 onward) has this built-in via M-x rename-file (and there is delete-file as well)