"Macmillan, one of the five largest publishers of trade books and
textbooks, is introducing software called DynamicBooks, which
will allow college instructors to edit digital editions of
textbooks and customize them for their individual classes.
Professors will be able to reorganize or delete chapters; upload
course syllabuses, notes, videos, pictures and graphs; and
perhaps most notably, rewrite or delete individual paragraphs,
equations or illustrations."

NYTimes