1. A method of maintaining annotations across versions of an electronic book comprising: receiving at an access device a version of an electronic book and a signal instructing the access device to correlate a set of annotations associated with a different version of the electronic book with the received version of the electronic book, the received and different versions of the electronic books each including at least one document file, wherein each annotation in the set of annotations includes a document file indicator corresponding to the at least one document file with which the annotation is associated; using the document file indicator to compare each annotation of the set of annotations with the received version of the electronic book in order to determine where the annotation should be inserted into the received version of the electronic book, wherein if the received version of the electronic book does not include a document file indicator that matches a document file indicator of the different version of the electronic book, the annotation associated with the document file indicator of the different version is inserted at the beginning of the received version of the electronic book; and, inserting each annotation of the set of annotations into a location of the received version based on the comparing.
1. A method of maintaining annotations across versions of an electronic book comprising: receiving at an access device a version of an electronic book and a signal instructing the access device to correlate a set of annotations associated with a different version of the electronic book with the received version of the electronic book, the received and different versions of the electronic books each including at least one document file, wherein each annotation in the set of annotations includes a document file indicator corresponding to the at least one document file with which the annotation is associated; using the document file indicator to compare each annotation of the set of annotations with the received version of the electronic book in order to determine where the annotation should be inserted into the received version of the electronic book, wherein if the received version of the electronic book does not include a document file indicator that matches a document file indicator of the different version of the electronic book, the annotation associated with the document file indicator of the different version is inserted at the beginning of the received version of the electronic book; and, inserting each annotation of the set of annotations into a location of the received version based on the comparing. 8. The method of claim 1 , wherein a copy of the set of annotations associated with a different version of the electronic book is stored on a server, and wherein the method is carried out when the access device is synchronized with the server.