Parkinsonism is a clinical syndrome characterized by motor symptoms like bradykinesia, tremor, and rigidity. It has multiple causes including Parkinson's disease, which is the most common form. Parkinson's disease is a neurodegenerative disorder caused by the loss of dopamine-producing neurons in the substantia nigra. The motor symptoms are diagnosed based on the presence of two of the four cardinal features - bradykinesia, tremor, rigidity, and postural instability. There is no cure for Parkinsonism currently, so treatment focuses on relieving the motor symptoms and managing non-motor issues.