Venetian blinds

For the desktop theming software, see WindowBlinds. A window blind or door blind is a covering for a window or door, usually attached to the interior side of a window. Blinds hide from sight (thus "blinding" a viewer of the window) or to reduce sunlight. Blinds have varying thermal effects: they can block unwanted heat of the summer sun and they can keep in heat in cold weather. But in both of these applications, they also reduce light to varying degrees, depending on the design. Many kinds of blinds attempt varying balances of blinding external viewers and allowing sunlight.
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