I've noticed that many (all?) style and class files have "documentation blocks" with a double comment character at the beginning of the line,
%% like so
instead of the usual style of comments,
% like so
Why is this done? Do some kinds of comments need the
%% for some preprocessing/automatic documentation generation/etc. - or is it just customary? Should I mix
% in the same file for different uses?
(Specifically, an answer to Make your own .sty files suggests single-comment-char comments, which added to my confusion.)