.markdown or .md

Holy religious wars Batman.

So this seems like something that should be very simple, I wouldn’t have thought about it or noticed it at all apart for the base blog created the two variations, the example jekyll blog post is welcome-to-jekyll.markdown but the about page is about.md

Now it doesn’t make a difference but I think a lot of programmers suffer a bit on the OCD front.

A google for which one to use brings up a world of debate, the creator reckons it doesn’t matter at all Gruber’s opinion

Too late now, I suppose, but the only file extension I would endorse is “.markdown”

Yet I think because of Github .md seems to be the most popular, it’s also way shorter ;) so I think I might go with that, I’ve ignored all the other options two is enough. I wonder why the jekyll site setup has both?