8.10 Gadgets that can have children
8.10.3 Tab controls
An instance of the class <tab-control> lets you define a sheet that contains several "pages" of information. Each page of information is displayed by clicking on the appropriate tab along the top of the sheet.
This children of a tab control are the pages of information themselves. Each child should be an instance of the <page> class. The various types of page available are described in Section 8.9 on page 521.