Not everybody knows exactly what ergonomic means, but it's getting to the point where everybody knows an "ergonomic chair" is better than just some plain old chair. Thus even Joe Newbie is more likely to buy the ergonomic chair than the chair that is not advertised as ergonomic.
The problem is stores and manufacturers are starting to put the word ergonomic in front of every chair they sell, whether it has anything to do with ergonomics or not. There is more to ergonomics than a little added cushioning in the seat.
So, What Is an Ergonomic Chair?
Ergonomics is the study of equipment designed with humans in mind, meant to reduce operator fatigue and discomfort. Specifically, an ergonomic chair should be highly adjustable, including not just a knob for lowering and raising the chair but adjustability in the back tilt and the height of the arm rests. An ergonomic chair should also have a sturdy frame (avoid plastic), a great deal of support, especially in the lumbar region, and padding that has some give and supports your body without losing shape.
Real ergonomic chairs cost hundreds of dollars. Look for manufacturers that specialize in ergonomics and are known for producing quality chairs. Examples are Herman Miller, Neutral Posture, and BodyBilt. Avoid gimmicky chairs (such as kneeling chairs and ball chairs) unless you have actually had the opportunity to try one and feel it's a good fit for your body. Remember, the chair that is comfortable when you first sit in it may not remain so after several hours.
Why and When Should You Consider Buying an Ergonomic Chair?
An ergonomic chair promotes good posture, reduces the fatigue that comes with sitting in one position for a protracted period of time, and it can even reduce the likelihood of developing Carpal Tunnel Syndrome and other repetitive stress injuries (many of these hand and wrist injuries start with poor posture at the computer).
Anybody who spends more than an hour a day at the computer should consider buying a good ergonomic chair. If you work 8 hours a day or more at the computer, you should definitely have a good ergonomic chair.