About Modifying Cells
For each type of cell, there are several ways to change the cell itself as well as the data it contains.
All formatting options are available in the Cell dialog, which can be accessed on the Home tab, click Cell. In addition, right-click a cell to display a context menu with formatting options that can be quickly applied. Cells may be formatted individually or in groups.
Certain cell options are applied globally as defaults to the document. Attributes such as underline weight, dash position, and currency position are defined in the Cell Options dialog. To access this dialog, on the Home tab, click Cell Options to apply cell defaults to the entire document.
For cells that are already part of a cell group, all properties set in the cell group can never be modified except by changing the cell group properties. See About Cell Groups for more information.