Windows may be divided into two categories, 'always-on-top' and ordinary. When a task is switched to, it is moved to the head of its category. For the following example, suppose there are no 'always-on-top' windows. Let "A" be the current window title. Hold down Alt and press and release Tab once, leaving Alt pressed. The window list comes up. "A" is guaranteed to be first in the list. Suppose the complete list is "A W Z E U B C". The selection cursor will initially be on "W". Suppose we want to switch to window "U". Without releasing Alt, press Tab three more times and then release Alt. Then hold down Alt and press-release Tab once leaving Alt down. The window list will now show "U A W Z E B C". Then Tab over to "E" and release Alt, selecting window "E". Press and hold down Alt and press-release Tab once leaving Alt down. The window list will now show "E U A W Z B C". Note that the windows switched to with ("E", "U", "A") are in order of how recently they were switched to. Now Tab over to "A" and release Alt. Press and hold down Alt and press-release Tab leaving Alt down. The window list will show "A E U W Z B C". The effect of this most-recently used behavior is that to return to the most recent task, Tab is pressed once, for the second most recent task Tab is pressed twice, and so on for all tasks. The priority of a window in terms of accessibility is how recently it was used. If "A" is now minimized, the list will become "E U W Z B C A", and if "Z" is minimized the list becomes "E U W B C A Z". Thus minimizing a window mimics the effect of not using it for a long time.