A tremor, or shaking, usually begins in a limb, often your hand or fingers. You may notice a back-and-forth rubbing of your thumb and forefinger, known as a pill-rolling tremor. One characteristic of Parkinson's disease is a tremor of your hand when it is relaxed (at rest). Slowed movement (bradykinesia).
The vertical bar is often called a ' pipe '. It is often used in mathematics, logic and statistics. It typically is read as 'given that'. In probability and statistics it often indicates conditional probability, but can also indicate a conditional distribution. You can read it as 'conditional on'.
A bar graph is a chart that use either horizontal or vertical bars to show comparisons among categories. One axis of the chart shows the specific categories being compared, and the other axis represents a discrete value.