Yard (Courtyard, Compound) and Persian Yard
This place has been utilized in houses at various features such as:
Courtyard as a sign of position limits.
Courtyard: unifying some elements of a house.
Courtyard connector of some spaces.
Courtyard to create an green happy surrounding.
Courtyard as artificial vent duct to facilitate passing the currents and winds.
Courtyard: an important element to organize various spaces.
Courtyard as secure and calm limit for family relaxation.
The reason, why this courtyard is appeared in architecture, as a necessary space, is not clearly defined, but it is said that the courtyard as regulator of air abstracts wind, creates a shadow and protects the solitude private life of inside family against the open unsafe atmosphere of the outside.