When you see this arrow 
(called the Dialog Box Launcher) in the lower-right corner of a group, there are more options available for the group. Click the arrow, and you'll see a dialog box or a task pane.
For example, on the Home tab, in the Font group, you have all the commands that are used the most to make font changes: commands to change the font, to change the size, and to make the font bold, italic, or underlined.
If you want more options, such as superscript, click the arrow to the right of Font, and you'll get the Format Cells dialog box, which has superscript and other options related to fonts.
