What are the two different gaze & switch modes?

There are two methods to execute the chosen Task. The method of choice is set from within the Windows Control Settings Dialog.
Gaze - Using the eyes to both control and execute selected Task.
Gaze & Switch - Using the eyes to control and using a mechanical button connected to device to execute the selected Task.
 
Select a Task from the Taskbar to execute. Gaze at your chosen task until it is highlighted as Primary, Secondary Selection, or Tertiary Selection.

For Gaze:

• Rest your gaze at the desired portion of the screen (or icon on the screen) to execute the chosen Task or where you want to execute the Task. An automatic zoom function is enabled which ends in the selection of the icon or execution of the task. Note: When using the Gaze method, you have to look back at the Taskbar to select a new Task before each task execution.

For Gaze & Switch:

• Single activation of the Switch - Use the zoom function to execute in the same way as with the Gaze method and according to the settings made in the Windows Control Settings Dialog
• Activate and hold the Switch – Use the zoom function to zoom continuously and end only upon the release/deactivation of the switch. 

Note: When Zoom Depth is set to Shallow in Windows Control Settings, no zoom is performed.