What's the difference between a quadrangle and a courtyard?

Generally speaking, the courtyards of ancient buildings in China are mainly compound courtyards, which is the basic grammar of China's group combination architecture language. The basic language forms of quadrangles are Sanhe Courtyard and Siheyuan Courtyard. Sanheyuan is a single building. After the building location is determined, two secondary buildings will be built on both sides of the facade, and the plane combination of the three buildings is "concave". The three can be connected through their own walls, or through corridors or walls with a distance. In addition, fences are set in front of the three buildings to connect the two secondary buildings to form a closed courtyard. The entrances and exits of Sanhe Hospital are often opened on the front wall, either in the middle or at one end, depending on their respective needs.

The difference between quadrangles and quadrangles is that the front of quadrangles is a wall, while the front of quadrangles is a building. This kind of house faces the courtyard, that is, the main house at the back is in the form of inverted seats, so some places are called "inverted houses" Most of the houses around the quadrangle are not connected, but there are gaps and a certain distance. In order to have the effect of enclosure, that is, to form a real quadrilateral, it is necessary to connect the gaps of the four. The contact here often uses verandas, and most of them are ingenious verandas.