The following symbols have both been introduced to me as a 'paragraph symbol'. With the help of ShapeCatcher and Wikipedia, I found out that
However, I've seen both of them used to indicate what part of a document is referred to. (e.g. § 4.2 refers to the second paragraph in the fourth chapter of a book, but I have also seen ¶ 4.2)
Are both of these uses correct, or not? In what ways are these symbols further used?