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An item (and its context) is visually highlighted on mouse over or by moving the keyboard focus on the item using one of the arrow keys (UP, RIGHT, DOWN, LEFT).
If an item is only highlighted, no details on it are shown anywhere in the interface - the visual marker merely makes it clear that the item could be selected. The reason we show no details is to prevent the interface from changing too rapidly, to keep it responsive and to prevent high load on the server.
A single item may be selected by clicking on it or by hitting the Enter keySPACE bar. Alternatively, for interfaces which allow selecting multiple items, a checkbox next to the item may be checked to select the item. In both cases, a stronger visual marker marks the items as "selected". In addition, any visible and enabled view for item details will refresh and show additional details on the item. To select multiple items, you repeatedly select single items until all the item you intend to select are selected.
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