The shutters are those parts of the window frames that mainly constitute a safety closure of the opening, and serve to graduate the intensity of sunlight inside the rooms. They are therefore used essentially in southern countries, where the need for protection from the sun's rays is most felt, especially in the summer season.

The origin of the use of shutters, at least in their current form, can be traced back to around the century. XVIII. However, this does not mean that previously this defense system was completely ignored; since real shutters, even if based on a different system from ours, were found during the excavations of Pompeii; the Romans also used sturdy wooden doors which were also adopted during the Middle Ages and which are still used today in rural buildings. During the Middle Ages, shutters made of massive stone slabs were also used.