Attention Deficit Hyperactivity Disorder (ADHD) is a neurodevelopmental disorder characterized by symptoms of inattention, hyperactivity, impulsivity, and emotional dysregulation. It is the most commonly diagnosed mental disorder in children, but it can also affect adults. Symptoms can vary widely and may include difficulty focusing, excessive movement, and challenges with organization. Treatment options often include behavioral therapy, medication, and educational support. For more detailed information, you can refer to sources like the National Institute of Mental Health and Healthline.