System and method for annotating an electronic document independently of its content

Abstract

A system, method, and apparatus for annotating an electronic document independently of its content is provided. According to one variation, a tablet and stylus-based computer is programmed with a document browser that permits a user to annotate documents viewed through the browser. The annotations are stored separately from the viewed document pages but are correlated with the pages such that when a previously annotated page is revisited, annotations relating to that page are retrieved and displayed on top of the page as an “ink” layer. Three different annotation modes are possible: ink, highlight, and erase. Each mode can be selected through a user interface supplied through the browser or through controls embedded in a document.

We claim: 
     
         1 . A computer-implemented method of annotating pages of an electronic document independently of the contents of the document, comprising the steps of:
 (a) displaying a page of the electronic document on a computer display device using a document browser that permits a user to move forward and backward among a plurality of document pages;   (b) detecting a selection of an annotation mode that permits the user to annotate the currently displayed document page;   (c) receiving annotation stroke input from a user input device indicating that the user has moved the user input device for a continuous distance about a stroke location on the currently displayed document page; and   (d) storing annotation stroke data based on the received annotation stroke input, said annotation stroke data comprising data corresponding to the stroke location and the movement of the user input device, wherein the annotation stroke data is stored in an annotation file associated with the user, the annotation file stored separate from the electronic document.