Effects of document-type?

The Quickbook docs for document-type list the names (book, article,
library, etc.) but gives no indication as to what the effects are.
Does a stylesheet change? Do other settings change?

See http://www.boost.org/doc/libs/1_48_0/doc/html/quickbook/syntax.html#quickbook.syntax.block.document

The best response would be if someone could update the docs, perhaps
by converting the list of names to a table showing the effect of each
name.

Thanks,

--Beman