Bar stools are a relatively modern development of an ancient form of seating. The exact origins of the stool are unknown, but evidence exists that they were used in ancient Egypt and China, possibly as a demonstration of social status. As small, folding seats, these stools were very portable, making them convenient to travelers. As the Romans conquered much of Europe, they brought with them bar stools to use at public houses, where they are still in use today.
The basic structure of a stool remains the same as it has for centuries. It consists of an essentially flat top supported by any number of legs. Most have been made of wood, but modern stools are often made from metal such as steel or aluminum. The seats can be plain or covered, usually with padding for comfort. Some even have backrests and armrests, depending on the style.
The use of stools at bars may have stemmed from convenience and conservation of space. Stools generally require less material and space than chairs, letting more people sit at actual tables. With the tables full, stools allowed establishments to add more seating for patrons with the bar itself acting as the table. Particularly for parties of one or two, this arrangement was convenient, not to mention closer to the alcohol. No one had to stand while they ate and drank.
Once other drinking and eating establishments caught on to their use, bar stools became the standard at diners and malt shops. Bar stools as home furnishings really came into vogue in the 1950s and 1960s, when chrome bar stools covered in bright vinyl bellied up to kitchen bars throughout the United States. This look still exists in some retro applications, but bar stool design, whether at home or out, is now open to whatever suits the consumer's fancy.