Jekyll, Liquid and Markdown, what's the connection?

Question

Markdown

I would like to know if it is possible not to use it when working with Jekyll at all?
In the picture below, on the left, you can see the structure of the template, as well as the post opened in the editor with the .md extension, which stands for Markdown.
Between the three dashes, variables are set, as I understand it, which can then be used when integrating using Liquid.
So, is it possible to somehow use the ability to pass variables to Liquid, which Jekyll uses without resorting to Markdown?
I would, for example, write posts on my own in Jade, for example, I don’t see any difficulty (apparently, they use MD as an analogue of Jade here?).
And in general, will Jekyll be able to put it all together somehow?
In general, I got confused in all this, and I have absolutely no idea how to google this. And I watched a lot of videos on YouTube.
Can someone provide a link where it says how it all works thoroughly?

Answer 1

Jekyll not only supports Markdown, but also HTML and Textile.