Jalousie windows and doors are very similar in principle to Parisienne shutters, in that the the upper section is louvred, within a solid frame. Whilst Parisiennes by and large provide supplementary cover, Jalousies are themselves the door or window.
The design is such that the louvres can be opened, adjusted to allow air flow without compromising security. An idea taken up readily in single story accommodation and extensions, such as mobile homes and garden rooms.
Since the early 1900s the idea and the system have been developed, now to a high level of engineering and design, used at high level and in award wining architecture.