Check the developer’s videos on Youtube. He gives some tips there. For instance, you can type “Greed” in the search field in that left-side log screen and it will show information about it on the log (though it doesn’t work for everything). If you see info for a card, it usually explains what the terms are in the detailed description.
As for your previous questions: most classes have two main damage types. And they all have strengths and weaknesses, which means nearly every one of them will have some difficulty facing certain enemies and certain resistances. In those times items can make a huge difference.