Opioid receptors are specialized proteins found in the brain, spinal cord, and other parts of the body. They play a crucial role in how we perceive pain and respond to stress. There are three main types of opioid receptors: mu, delta, and kappa. Each type has different functions and effects when activated by natural or synthetic substances. When opioids, such as morphine or heroin, bind to these receptors, they can produce feelings of pain relief, relaxation, and euphoria. However, this interaction can also lead to side effects and the potential for addiction, making understanding opioid receptors important for both medical and public health perspectives.