You can move back and forth through topics you have already viewed or move back and forth through topics as they appear in the Contents list:
To move back and forth through topics you have already viewed, click the Back and Forward buttons, shown in Figure 1-1.
To navigate back and forth through topics as they appear in the Contents list, choose Go > Previous Contents Entry or Go > Next Contents Entry. You can also use Ctrl + v to go to the previous topic and Ctrl + f to go to the next topic.