I am writing a fantasy novel and there are many elements that will need explaining, such as precious items, cities, creatures, and certain terms.

A glossary won't suffice and I'm stuck as to what this "section" should be called and where it should be placed. I'm thinking it should be placed in  the back matter as people may read it first if it is included in the front matter, thus eliminating any "surprise".

What is it called and where is the best place for it?

**UPDATE:**

An example of this would be in the "Miss Peregrine" novels where there is a section at the beginning of the books which explains who the characters are and also **what** some of them are (see "[ymbryne][1]", for example).

Some people feel that such a feature within a book would detract from the story, but I am of the view that such information could be helpful if there are so many elements that it would require the reader to remember a lot of extra information.  Also, characters explaining things is all well and good, but as my story contains a lot of unique, world-specific elements, it would mean that a significant portion of my book would be taken up by characters explaining things; however, there will of course be explanations by characters about the key elements within the story - the appendix/addendum would be for reference, briefly reiterating what each specific thing is and/or what it does.


  [1]: http://thepeculiarchildren.wikia.com/wiki/Ymbryne