Pain sensation is a complex experience that alerts the body to potential harm. It occurs when specialized nerve endings, called nociceptors, detect damaging stimuli, such as extreme heat, pressure, or chemicals. These signals are transmitted to the spinal cord and then to the brain, where they are processed and interpreted as pain. The perception of pain can vary widely among individuals due to factors like genetics, emotional state, and previous experiences. Pain can be classified into two main types: acute pain, which is short-term and often linked to injury, and chronic pain, which persists over time and may not have a clear cause.