16. The system for publishing and distribution of claim 14 wherein: the host computer is capable of receiving one or more revisions to one or more segments of the one or more educational works, and storing the one or more revised segments to replace one or more previously stored segments.
17. The system for publishing and distribution of claim 16 wherein: the host computer is capable of generating an email message to a student client computer from which an order for purchase of a segment has been received when a revision of the segment is stored, the email message including an alert that the revision of the segment has been stored.