Ergonomics is concerned with the ‘fit’ between people and their technological tools and environments, basically about organizing the workplace to fit the worker.
The origin of the word comes from Greek: "Ergon" is work and "Nomos" is natural laws. This means re-adjusting your equipment and workplace to fit your needs, and becoming more aware of your posture in your work environment.
Having proper ergonomics at your workplace is crucial to having proper posture and to help prevent Repetitive Strain Injuries (RSI), other ailments such as headaches, eye strain, back and neck strains, to help reduce stress and increase productivity. Whether you work at a lumber mill or as a computer programmer, ergonomics plays an extremely important role in helping you to do your job efficiently as well as with the least amount of stress/strain on your body.
More information available at: Wikipedia