...
A single item may be selected by clicking on it, touching it or by hitting the SPACE bar when it has the focus. If an interface supports selecting multiple items, it thus shows a checkbox next to an item. Thus, alternatively, this checkbox may be checked to select the item. In both cases, a strong visual marker around the item signals its selection.
So, while an item may be selected without checking its checkbox if you use mouse or touch input, its checkbox is always toggled if you select the item using the keyboard.
In addition, any visible and enabled view for item details will refresh immediately and show additional details on the just selected item.
...