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 method for visualizing a set of data. Simple bar graphs compare data with one independent variable and can relate to a set point or range of data. Complex bar graphs compare data with two independent variables. Either type of graph can be oriented horizontally or vertically.