The first is a page- based elliptical view that shows an entire document simultaneously and provides multiple navigation mechanisms. We have used it to develop a tutorial document. The second technique employs an inverted triangle view so that any size document can be presented in the same amount of space.
Access is via zooming rather than panning.
It is difficult to show very much of a document at a time and this reduced view makes it difficult for users to sense where they are within the document. Several techniques have been developed to address these problems. More traditionally, scrollbars are used to pan through long documents and hyperlinks provide quick access to parts of the document linked to words or phrases. The first page is placed at the bottom. Middle pages are drawn at a smaller scale along the top edge of the ellipse.