Tilt and turn windows work by the simple turning of a single handle. There are three different positions for the handle, each of which allows unique functionality. When the handle is pointing upward and the window is closed, at least five steel locking pins keep the window securely shut. 

When the handle is turned by 90 degrees, into the horizontal position, the window starts operating differently than a door. The hinge in the upper corner is disconnected. At the same time, a hinge in the other bottom corner of the vent is connected to the vent. The vent suddenly tilts inwards, held by the hinges the bottom corners. That is possible because of an ingenious design: One of the hinges on the lower corner operates in two directions, supporting both tilt and turn. The other two hinges support only tilt or turn but are only connected to the vent if the window handle is in a certain position. When the handle is turned by 180 degrees pointing downwards, the window functions a lot like a normal door. In this position, the locking pins are unlocked and the window vent turns open, held by hinges on one side of the window. There is one hinge on the upper corner and one on the lower corner, just like you would see it on a regular door. 

With that, the whole window can open like a door or just tilt inward by 10 to 15 degrees, moving along the hinges on the bottom of the window and allowing easy ventilation without having to worry about intruders or weather changes.