[Group Name] field
Used to specify the name of the group to which a radio button belongs. Within any one group, you can select only one radio button.
[Value] field
Used to specify the data to be sent to the server when this radio button is selected.
[Initial State] group
[Selected] radio button
Used to set the initial state of this radio button (when the button is first displayed) to on.
[Disable] check box
Used to disable a radio button. This is not applied to the edit area.
[Read-only] check box
Used to make a radio button read-only. This is not applied to the edit area.
What is a radio button?
A radio button is used when you want to select only one item from a group of two or more. Note that these items must be assigned the same group name. If items have different group names, multiple selections must be made since different items each have different actions. If you want to allow multiple selections, use check boxes.