21. A computer-implemented method of playing back evolution of a segment of an electronic document, comprising: presenting an electronic document; retrieving a revision history associated with the electronic document; presenting a graphical control, the graphical control allowing to select a graphical region within a visible portion of the electronic document; selecting the graphical region; choosing a first and a second reference points from the revision history, wherein the first and the second reference points are applicable to the chosen graphical region; determining revision points between the first and the second reference points; traversing the determined revision points and generating a graphical representation of the electronic document at each revision point; constructing an animation sequence comprised of the graphical representation of the electronic document at each revision point, wherein the animation sequence is created separately from the document; and displaying the animation sequence as animation-sequence-playback.
29. The method of claim 21 , further comprising disallowing the user to edit the document during the playback of the animation sequence.