Contextual Menus or Contextual Tabs are new to PowerPoint 2007. Instead of scrolling through the longer menus of previous versions of PowerPoint, once a topic is accessed, the Ribbon changes to objects pertaining to that option.
For example - After choosing to insert a picture from the Insert ribbon, the ribbon changes to show more graphical options that can pertain to this picture. Several style layouts are shown, but more options can be seen by clicking the arrow to the right of the layouts. This expands the selection choice. In many cases, you will see a preview of your choice. It is not necessary to apply the selection first.
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