Type of tremor that is sometimes to referred to as a benign tremor and is the most common. Is mild and non progressive in some people, and in others is slowly progressive starting on one side of the body and spreads to effect both sides within 3 years. Hands are most often affected but the head (yes-yes/no-no motion), voice, tongue, legs and trunk can also be involved causing mild gait disturbances. Frequency may decrease as a person ages but severity may increase, affecting the person's ability to perform certain tasks or activities of daily living. Affected by emotion, stress, fever, physical exhaustion/low blood sugar but is not associated with any known pathology.