One of the basic pieces of furniture, a chair is a type of seat. Its primary features are two pieces of a durable material, attached as back and seat to one another at a 90°-or-slightly-greater angle, with usually the four corners of the horizontal seat attached in turn to four legs—or other parts of the seat's underside attached to three legs or to a shaft about which a four-arm turnstile on rollers can turn—strong enough to support the weight of a person who sits on the seat (usually wide and broad enough to hold the lower body from the buttocks almost to the knees) and leans against the vertical back (usually high and wide enough to support the back to the shoulder blades). The legs are typically high enough for the seated person's thighs and knees to form a 90°-or-lesser angle. Used in a number of rooms in homes (e.g. in living rooms, dining rooms, and dens), in schools and offices (with desks), and in various other workplaces, chairs may be made of wood, metal, or synthetic materials, and either the seat alone or the entire chair may be padded or upholstered in various colors and fabrics. Chairs vary in design. An armchair has armrests fixed to the seat; a recliner is upholstered and under its seat is a mechanism that allows one to lower the chair's back and raise into place a fold-out footrest; a rocking chair has legs fixed to two long curved slats; and a wheelchair has wheels fixed to an axis under the seat.
An office chair, or desk chair, is a type of chair that is designed for use at a desk in an office. It is usually a swivel chair, with a set of wheels for mobility and adjustable height. Modern office chairs typically use a single , distinctive load bearing leg (often called a gas lift), which is positioned underneath the chair seat. Near the floor this leg spreads out into several smaller feet, which are often wheeled and called casters. Office chairs were developed around the mid-19th century as more workers spent their shifts sitting at a desk, leading to the adoption of several features not found on other chairs. There are multiple kinds of office chairs designed to suit different needs. The most basic is the task chair, which typically does not offer lumbar support or a headrest. These chairs generally cannot be sat in for more than a couple hours at a time without becoming uncomfortable, though they often offer more room to move than higher-end chairs. Mid-back chairs offer fuller back support, and with the right ergonomic design, can be sat in for four hours at a time or longer. Egnormic chairs in this category, such as the Herman Miller Aeron and the Steelcase Leap are comfortable for long periods. Some mid-back chairs in particular offer customization options that can allow for a headrest to be added. Executive or full-back chairs offer full back and head support. Many executive chairs are designed to be sat in for eight or more hours at a time. These are typically the most expensive office chairs.
The computer chair is a kind of chair, which has various classifications and has been widely used in people's work, study and production places. It has certain ergonomics and is beneficial to health. According to the function, it can be generally divided into two types of computer chairs: (1) Ordinary computer chairs: computer chairs can usually only be used by ordinary users for daily use, short-term Internet access, etc.; (2) Ergonomic computer chair: The so-called ergonomic computer chair is ergonomically designed, and the way of use is as suitable as possible for the natural form of the human body, so that the person who can use the tool does not need any active adaptation to the body and spirit when working, so as to try to use it as much as possible. Reduce fatigue caused by using tools. This type of computer chair must meet the following conditions: ①. The headrest is adjustable; ②. The armrest can be raised and lowered, and can be raised and lowered in multiple stages, so that the hands and body can maintain the best position with the ground and computer desk; ③. The backrest can better fit the back, and can effectively relieve spinal fatigue when working at a desk for a long time; ④. With lifting function; ⑤. The length and width of the seat cushion and the height of the chair must be specially customized according to the users. For example, the height and weight of Asians are usually lower than those of Europeans, so for Asians, there must be a certain standard, and for Europeans, there must be another set of standards; ⑥. There are thickened explosion-proof steel plate. Any ergonomic computer chair must be people-oriented, starting from people and taking personal safety as the first element, the main role of explosion-proof steel plate is to strengthen the protection of personal safety; ⑦. The pneumatic rod must be certified by SGS International; ⑧. The load-bearing capacity of the tripod should be greater than or equal to 500kg. The test method can use the car to press the tripod one by one to confirm the load-bearing capacity.
A gaming chair is a type of chair designed for the comfort of gamers. They differ from most office chairs in having high backrest designed to support the upper back and shoulders. They are also more customizable: the armrests, back, lumbar support and headrest can all be adjusted for comfort and efficiency. The gaming chair gained popularity with the rising influence of Twitch and other online game streaming websites. Having to sit at a computer, playing games for hours on end attracted streamers to purchase gaming chairs. There are three main types of gaming chairs. These include PC, platform, and hybrid gaming chairs. PC gaming chairs are the most popular and well-known. They resemble office chairs, but include a headrest, lumbar support, as well as adjustable armrests.Platform gaming chairs are popular among console gamers. This is because they are meant to rest on the floor and are efficient for television gaming. These chairs normally resemble recliner chairs.Lastly, hybrid gaming chairs share characteristics of both PC and platform gaming chairs. They are often mounted on a swivel base, but still include the shape and style of a platform chair.