The term "biofeedback training" came into use, around 1969, when it
was modified to be a useful tool in the teaching and learning of
automatic adjustment processes that involves training. In a restricted
sense, it is possible to conceptualize feedback through an etymological
view. From the radical feed, alimentary, and the radical back, back,
originate a feedback from a system. In popular language, the term
feedback can also be considered as providing information about the state
of a system. In educational and business environments, biofeedback
training is a tool for the development of deep relaxation and stress
management, processes that are important in preventing stress-related
illnesses. In all applications, the goal of biofeedback training is
self-regulation – learning how to control both physical and mental
requirements for better and healthier functioning.