1. An information processing apparatus comprising: an operation input unit that receives an input of a user to control display of an electronic document; an electronic document display control unit that displays a page of the electronic document on a screen; an electronic document operation control unit that changes the display of the page between an expansion-display that displays expanded display of a portion of the page at a magnification and a reduction-display that displays glancing over the entire page; an annotation operation control unit that adds at least one annotation object on the portion of the page when the page is displayed in the expansion-display; and an electronic document data holding unit that holds page data of the page of the electronic document, wherein the annotation operation control unit stores the magnification for the expansion-display that displays a part of the electronic document when the annotation data is added to the portion of the page, and wherein the electronic document display control unit, in response to the operation input unit receiving an input of the user to select the at least one annotation object, changes the display on the screen from the reduction-display to the expansion-display having the magnification stored by the annotation operation control unit.
1. An information processing apparatus comprising: an operation input unit that receives an input of a user to control display of an electronic document; an electronic document display control unit that displays a page of the electronic document on a screen; an electronic document operation control unit that changes the display of the page between an expansion-display that displays expanded display of a portion of the page at a magnification and a reduction-display that displays glancing over the entire page; an annotation operation control unit that adds at least one annotation object on the portion of the page when the page is displayed in the expansion-display; and an electronic document data holding unit that holds page data of the page of the electronic document, wherein the annotation operation control unit stores the magnification for the expansion-display that displays a part of the electronic document when the annotation data is added to the portion of the page, and wherein the electronic document display control unit, in response to the operation input unit receiving an input of the user to select the at least one annotation object, changes the display on the screen from the reduction-display to the expansion-display having the magnification stored by the annotation operation control unit. 2. The information processing apparatus as claimed in claim 1 , wherein the at least one annotation object comprises a plurality of annotation objects, and wherein the electronic document display control unit, in response to the operation input unit receiving an input of the user to select the plurality of annotation objects, divides the screen into a plurality of screens on each of which the page of the electronic document is displayed based on the magnification and the portion of the page stored in the electronic document data holding unit corresponding to each of the plurality of annotation objects.