What in the world is Homeostasis??

In middle school, teachers begin teaching us about homeostasis, but the question is; do we really understand it?  In fancy terms, homeostasis is the ability to maintain a relatively stable internal environment in a constantly changing outside world.  The process of homeostasis involves chemical, thermal, and neural factors that interact.  In simple terms, I understand homeostasis as the body's ability to stay cool and collected internally while the outside world is constantly changing.  Homeostasis involves many different things like receptors, a control center, and effectors. 
Receptors are responsible for keeping an eye on the body and responding to the changes it makes.  After the receptors see what the body needs it forwards it to the control center.  The Control Center gains the information from the receptors and it sets the range at which a variable will be maintained.  The control center makes the decision of an appropriate response to the stimulus.  Many scientists consider the control center as the brain in homeostatic mechanisms.  The control center sends signals to an effector, which can range anywhere from muscles to other structures that get signals from the "brain".  When the effector receives the signal, changes can occur to correct the difference by either increasing it with good feedback or decreasing it with negative feedback.

When homeostasis is disturbed, our bodies try to fix it by changing one or more physiological processes.  This helps us adapt to stress which includes activating the Hypothalamic-Pitauitary-Andrenal Axis with the nervous system and endocrine reactions of our bodies.  This can cause psychological distress and possibly even psycho-somatic disorders.

Diagram of homeostasis (:

Sources:
http://www.biology-online.org/dictionary/Homeostasis

http://en.wikipedia.org/wiki/Human_homeostasis