In recent years, great progress has been made in our understanding of the mechanisms underlying pain and in the treatment of people who complain of pain. Pain is probably the most common symptomatic reason for seeking medical attention. All of us have headaches, burns, cuts and other pains at some point during our childhood and adult life. Pain can be classified into three areas depending on its cause, location and duration. There are organic and psychogenic, peripheral and visceral and acute and chronic pain. Valid and reliable pain assessment is essential for effective pain management. Therefore, the nurse should be sufficiently educated in order to use various instruments to carry out proper assessment and interventions to reduce the patient's pain. Over the past 2 decades, the assessment and treatment of pain in children and adults has improved, thanks to the development of age-appropriate pain assessment tools and a better understanding of the role of analgesics in children and adults. The most common analgesics used in the treatment of pain in adults and children are opioids and non-opioids. Pain patients can spontaneously use a wide variety of drug-free methods to control their pain. Before suggesting or instructing patients in the use of drug-free techniques, nurses/technicians should be aware of the patient's effective and preferred methods. Treatment of patients with pain must be holistic. The correct assessment of pain helps a lot in the diagnosis itself, the course of treatment and the improvement of the patient's functional status.