ADHD is a neurological disorder that causes inattentiveness, hyperactivity, and impulsiveness. It has long been misunderstood but researchers have made progress in understanding its causes and symptoms. While low dopamine levels were thought to be responsible, recent studies suggest it may be due to faulty brain development. ADHD often begins in childhood but can continue into adulthood. Proper support from family and friends can help improve self-confidence for those living with ADHD.