A seat is a seat with a backrest and sometimes armrests. In ancient times, people sat on the floor. There were no chairs. "Chair" was originally the name of a tree.
       Classification according to use: airport seats, car seats, bus seats, family seats, restaurant seats, child safety seats, leisure seats, etc.
       Classified by material: aluminum alloy seats, stainless steel seats, iron seats, wooden seats, and seats made of other materials.