Plains are found in low-lying areas that barely have any difference between their highest and lowest points. They are generally formed by the phenomena of erosion and deposition caused by the running water of rivers. The silt and alluvium brought by the rivers result in fertile soil, which, in turn, promotes agriculture in these areas. As a result, agriculture is the prime occupation of people living in plains. Due to this, these plains are densely populated. It also results in the growth of the service sector that aims to provide good facilities to the people residing in these areas.