In the very early stages of design, you often want to create prototypes that show a broad swath of what the eventual Web site will support. These horizontal prototypes might show the top-level pages, but without much depth behind them (see Figure 4.13). The homepage might have all the links you expect to have, and each will take you somewhere, but any links from those second-level pages that implement specific features will not exist yet. These prototypes are good for making sure the basic features of the site are present and organized logically.