The chair (from the Latin sella) is a piece of furniture that usually has a backrest, generally has two, four or five supports and its purpose is to serve as a seat for a person.[1]​ Chairs can be made with different materials: wood, iron, wrought iron, plastic or a combination of them to guarantee their hardness.

Depending on their design, the chairs can be classic, rustic, modern, office, etc. Those that are wide, with a somewhat high backrest, with arms and a rocker are called armchairs. Those that also have arms but are narrow are called seats, such as dining room or theater seats. Those that are very comfortable, with arms and a low backrest, are called armchairs or sofas.

The oldest representations of chairs are found in ancient Egyptian, Near Eastern and classical Greek art.[2]​ In the century BC. C., the Greeks invented the Klismos, a chair with curved legs and backrest. These chairs are omnipresent in Greek art of that time, in which they serve as seats for all types of characters.[3]​.

At the beginning of the first Egyptian dynasty (ca. 3185 to 2925 BC), carpentry developed rapidly, probably thanks to the proliferation of copper tools. The wealthiest homes began to be equipped with beds, chests, chairs and stools, sometimes decorated with copper or ivory elements. The legs of the furniture were usually carved in the shape of the legs of domestic animals.[4] The most humble homes did not have any chairs, or only for the most important person in the family, while moderately wealthy families had chairs painted like those of wealthy people, but of much lower quality.

In ancient Rome, consuls and important personalities had a curule chair, which was reserved for them and which they carried with them on their trips. It was a backless seat, made of ivory or inlaid ivory, quite high, with legs curved and crossed in the shape of an X.[5]​.

In China, according to sinologist Donald Holtzman, the chair was introduced at the beginning of the Christian era, around the year 175 AD. C. Emperor Ling, fond of objects of Western origin, was the one who started the fashion. These chairs were used outside the house without further ceremony, for centuries. These were folding chairs, the only true seat used by the Chinese (apart from couches and stools) until the development of fixed-frame chairs between 750 and 960.[6]​.

During the Middle Ages in Europe, humble people still owned very few chairs, which were too expensive for them. That is why they used to use benches and stools as seats, or many other domestic objects, such as chests.[2] During the Renaissance, the chair began to be used in the wealthiest homes, but it was not until the century that it became a popular piece of furniture in Europe. In the late 1880s, chairs became common in American homes, with each family member owning a chair to sit in at dinner.