A Container control is any control into which other controls can be added to form logical groups of controls. Once controls are added to a container, they can be easily moved, copied, deleted, disabled, or hidden as a single group.
In addition, Container controls can be nested. For example, a category box control can contain a group box control which, in turn, can contain multiple panel controls.
The top-most control in every custom form is the Form. Any control added to the form is contained, directly or indirectly, within the Form Container control.
In addition to the Form, the following Container controls are available in the Form Builder: