Chairs are pieces of furniture used for sitting. They are provided with a back rest and sometimes even an arm rest. Chairs can be used by one person at a time. A chair is raised above the ground with the help of four legs. Chairs are designed according to ergonomic specifications as well non ergonomic functions such as size, stack ability, fold ability, weight, durability, stain resistance and artistic design. Chairs designed according to ergonomic designs distribute the weight of the occupant evenly all over the parts of the body. Chairs that are too high make the feet dangle and put increased pressure on knees. Reclining seats and backs shift the weight to the occupants back.