A small box to the left of a choice, when the check box is checked a checkmark or a X appears in the box. When the item is not checked, the box is empty.
These controls toggle a choice. When the choice is true, the box is checked. When the choice is not true, then the box is unchecked. Use the SPACE BAR to toggle the check mark on and off. When you are in a group of check boxes, you can press your arrow keys or tab between the choices.