A back yard (or backyard) is a yard that is located behind of a house, common in suburban developments in the Western world.
In cold-weather regions, it is economical in low land value regions the backyard is used for vegetable gardening during summers and allowing strongly demanded sunlight to enter house windows from a low horizon angle during winters.
As land value increases, houses are built nearer to each other. In order to preserve some of the open land, house owners may choose to allow construction on the side land of their houses, but not build in front of or behind their house in order to preserve some remnants of open surrounding land. The back area is known as the back yard. The front area is known as the front yard.
In Australia, the back yard of a property would traditionally contain a fowl run, outhouse, vegetable patch, and woodheap. More recently, these have been replaced by outdoor entertainments such as a barbecue and swimming pool. But, since the 1990s, the trend in Australian suburban development has been for back yards to disappear as the dwellings now occupy almost all of the building plot.