The courtyard house can be found in almost any culture and climate where the summers can be uncomfortably hot. Here are some charming courtyard houses from Syria. 
Courtyards typically take up about 25-40% of a building plot, so to economize on valuable urban space it is important to build right to the edge of the plot. Depending on the height of the building, different sized courtyards are necessary. Bigger buildings have more than one.
In Libya two houses were compared: in the summer outside temp ranged between 20°C-40°C. The temperature inside the traditional courtyard house remained almost constant at 28°C, while inside the modern detached house it ranged between 34°C-39°C. Unlivable without AC.
In arid climates, trees provide valuable shade during summer and in the winter the bare trees let the sun warm the rooms of the courtyard house. Fountains can be added to provide additional evaporative cooling.
The building surround the courtyard itself is also important, since they rely on inert mass to even out temperature differences between day and night, and different parts of the house. A trad house has about twice as much mass a modern house. Easy if you build with adobe, stone.
Most courtyard houses are built more or less symmetrically, but in arid hot climates you tend to want to find a good balance between sunlight and heat, hence the south west of the courtyard house usually have more space.
As with any traditional architecture, courtyard houses are extremely versatile: they can be private homes, government offices, hospitals, shops, restaurants, inns, hotels, schools, university campuses, religious centers, workshops, factories, swimming pools, orchards, etc.
"The courtyard is more than just an architectural device for obtaining privacy and protection. It is, like the dome, part of a microcosm that parallels the order of the universe itself." — Architecture for the Poor: An Experiment in Rural Egypt,
Hassan Fathy, 1969, 2010
Hassan Fathy, 1969, 2010
Here is a thread on Roman courtyards, and a little bit on tropical courtyards.
