Group sections, or groups, enable you to group report detail according to certain categories. In the previous example, itemized sales in the Detail section are grouped by customer.
Groups also enable you to summarize data when the group changes. For example, you can total the sales for each customer. Whenever you define a group, the Report Writer Designer application automatically inserts a group header and group footer section to contain the detail section the group encloses.
For more details about creating and using groups, see "Creating Groups", later in this chapter.