Latin and Greek letters are used in mathematics, science, engineering, and other areas where mathematical notation is used as symbols for constants, special functions, and also conventionally for variables representing certain quantities. Some common conventions: * Intensive quantities in physics are usually denoted with minusculeswhile extensive are denoted with capital letters. * Most symbols are written in italics. * Vectors can be denoted in boldface. * Sets of numbers are typically bold or blackboard bold.