In this course you must be able to do conversions from one unit to another within the metric system. For example you will have to be able to change a measurement made in milliliters into liters, or a measurement made in meters into centimeters, or a measurement made in kilograms into grams or milligrams. To do such things, you need to know conversion factors that relate the different units.  In this section we will deal with metric units, including the prefixes used with them, and their use as conversion factors.