9-grid hot pot is a type of Chongqing hot pot. Even though there are 9 grids in the hot pot, the soup base in all 9 of the grids is the same. It is said that the 9 grid hot pot was invented due to scarce resources. It allowed strangers to eat from the same pot using his own individual grid. This type of arrangement made sense both economically and practically for people with limited resources. These days of course people only eat hot pot with friends and families, or at least people they know. They still use the 9 grids, but instead mainly to cook different foods. This helps to cook foods that have different temperature and time requirements. It also helps eaters find a particular food item more easily if they know its location within the grid.