Figure 1-6. The Reference panel
For example, the O'Reilly HTML Reference provides a drop-down list of HTML tags. Selecting a tag displays its definition, compatibility, description, formatting requirements, and use within the Document Object Model (DOM) for both Microsoft Internet Explorer (IE) and Netscape Navigator (NN).
The arrow at the upper-right side of the Reference panel opens a pop-menu. The menu lets you change the font size of the text; it also includes a link to O'Reilly Books Online (the O'Reilly Safari subscription service).