Parkinson's disease is a progressive neurological disorder that affects movement. It occurs when nerve cells in the brain, particularly those that produce a chemical called dopamine, begin to break down. This leads to symptoms such as tremors, stiffness, and difficulty with balance and coordination. People with Parkinson's may also experience changes in speech and writing. While the exact cause of Parkinson's is unknown, it is believed to involve a combination of genetic and environmental factors. Treatments, including medications and therapies, can help manage symptoms, but there is currently no cure. Ongoing research aims to better understand the disease and develop more effective treatments.