Major depressive disorder (MDD) is a mental health condition characterized by persistent feelings of sadness, hopelessness, and a lack of interest in activities once enjoyed. It can affect daily functioning, making it difficult for individuals to work, socialize, or take care of themselves. Symptoms may also include changes in appetite, sleep disturbances, and difficulty concentrating. MDD can occur at any age and may be triggered by various factors, including genetics, brain chemistry, and life events. Treatment options often include psychotherapy, medication, or a combination of both, aimed at alleviating symptoms and improving quality of life.