ELI5: Explain Like I'm 5


Tremor is shaking or trembling in part of your body. It is often caused by a medical problem like Parkinson's disease or multiple sclerosis. It can also be caused by stress or certain medications. People who have tremor may have shaking or trembling in their hands, arms, head, face, legs or voice. It can happen when you are relaxed or when you try to do something.