Marking something up in a book would mean underlining or highlighting a text. In that sense I am finding it difficult to grasp the reasoning behind the name HTML(Markup).
As a side note, I am puzzled that, isn’t CSS the language that actually marks up the texts and other items in a webpage? Then why would HTML, the language of tags, be called a markup language.
I appreciate your time for reading this, feel free to point me towards resources where more information about this reasoning can be found.
have a good time!