Pain is an experience which everyone has felt at some point of time. Pain can be considered as the body's way of signaling that something is not right.
It is a kind of internal alarm that warns us that something in the body is not working well and calls for attention.
Reaction to pain is not a reliable indicator of its intensity as the ability to tolerate pain varies markedly from person to person. Some people may tolerate even severe pain without complaint, while others may complaint even if the pain is not intense.
According to the International Association for the Study of Pain, pain can be defined as "an unpleasant sensory and emotional experience associated with actual or potential tissue damage."