What is each element used for?

Yes, like a table that lists out in the first column, for example, how to use "<TEXT>", "apiname", "b", "Boolean", "cite", "cmdname", "codeblock", "codeph", "data", "data-about", "dl", "draft-comment" etc.  In the second column it would say in the "b" row, that this element means "bold" in the third collumn it would say "used when you want to bold certain text", next to "p", 2nd column: "Paragraph", 3rd column: "this element is used to create a new paragraph".

There are so many elements taht I don't know what they are or do. Such as "draft-comment", I figure it might publish in certain outputs that are not drafts, or only show up in a published output of certain draft types? But, I don't know what these rules are. I have trouble finding the correct EDD in all the support files. I'm not very good at reading an EDD. I have a difficult time figuring out which EDD (if I find them in the first place) is being used in the document that I have open. And, when you are in the EDD, they don't necessarily tell you what the word actually means, so the coding doesn't really make sense. Example: "ph", "fm-data-marker", "codeph", "msgnum", "parmname", "q", "screen". These mean nothing to me, and I'm trying to understand, but am unable to find a reference that is useful.

Thanks.