Window blinds are a type of window covering, nearly always found on the inside of the window. They serve the purpose of blocking out external light (hence the name blind), as well as hiding the inside of the structure from exterior viewing.
Window blinds are slatted, consisting of a number of long horizontal or vertical strips/slats attached in rows. In the modern world, window blinds are made of metal, vinyl, wooden and fabric varieties. The slats are usually connected with string such that they may be turned to either allow light to pass through them by becoming parallel with the window-sill, or else turned flat to block light from the outside. Usually the turning of the slats is accomplished by rotating a metal or plastic piece found at the upper-corner of the blinds. A string or pull allows the blinds to be raised, as well, removing them entirely from obscuring the window. There are also several types of window blinds that use a single piece of material instead of slats.10>