Once upon a time there were lands called ENVIRONMENTS. Every land had its own unique set of things. There were LIVING and NONLIVING things. Nonliving things, like tools, machines, chairs and tables, were called OBJECTS.
One living thing was called a HUMAN. A human performed ACTIONS and made CONTACT with objects in the environment. Some of these contacts were COMFORTABLE and others were UNCOMFORT ABLE.
Humans needed and wanted the contacts to be comfortable and actions to be efficient. The human therefore aimed for the RIGHT FIT when making the contacts. Some contacts were good (COMFORTABLE AND RIGHT) and some were bad (UNCOMFORTABLE AND WRONG).
Humans, actions, objects and contacts were studied to come up with rules and guidelines to get the right fit. This was called ERGONOMICS. Further, when some object, like a chair, was designed humans spoke of it having good ergonomics (comfortable and easy to use) or bad ergonomics (uncomfortable to use).
Ergonomics is the right fit between a human and other humans and objects in a particular environment. Bad fit = Discomfort and possibility of getting hurt. Good fit= Comfort and much lower possibility of getting hurt.
Use ergonomics in your life today!