The idea of producing school and university textbooks as wikis (i.e. as free and editable online texts) is slowly starting to gain momentum. Dave Cornier lists some pros and cons. The great thing about publishing a textbook as a wiki is that users (e.g. students and lecturers) can contribute to the text and so help to improve it and keep it current. Direct editing of the text need not be completely open (as is the case with wikipedia) – there could be different types of contributors, such as editors, chapter authors, box authors, and people who are allowed to comment or add margin notes. One way for textbook authors to make some money out of this form of publishing would be to sell printed copies of the book to those who don’t have good internet access, or who prefer to use a hard copy.