Does the DOI have any meaning embedded in the numbers?
No! In fact the DOI’s flexibility lies in the fact that it is a “dumb” number; it can then be used to denote all kinds of “objects” for which no standard numbering scheme exists: individual chapters, illustrations, prefaces, tables, etc. In the case of a whole book at the title level the ISBN is used as the suffix, but the DOI can be used to identify and link to any kind of “object” and any level of “granularity.” It is already being used (in addition to books) to identify “objects” as diverse as images, online courses, business school case studies, articles, etc.