A pre-order is an order you can make before an item is in stock and available for delivery. Wikipedia describes it as "An order placed for an item that has not yet been released. The idea for pre-orders came because people found it hard to get some items in stores because of their popularity or availability".
Generally, a Pre-Order is an item that is new to the marketplace and we have already placed an order with our suppliers/manufacturer for it. Listings are created when these items are - usually - in its manufacturing process. The pictures are taken from samples/prototypes. The finished product may vary in design, color, details and/or package contents. Please be ready to assume these risks before placing your order.