With my current knowledge, I can use commands such as
autocmd FileType markdown colorscheme zen to set a colorscheme for a particular type of file.
I have a need to use a colorscheme for all those files without a suffix, e.g.,
I did some research online, but didn't find relevant information.
Perhaps there is a name for this kind of file in vim, or at least a name for all the other files that are not in vim's
FileType detector range.
What is it?