The document discusses the metric system of measurement. It explains that the metric system uses prefixes like kilo, centi, and milli that are multiples of ten. It then defines common metric units of length, mass, and liquid volume. Meters measure length, grams measure mass, and liters measure volume. Examples are given for the size of a meter, kilogram, and liter. The document concludes by asking questions to test understanding of matching the correct metric unit to measurements in everyday contexts and changing between metric units by multiplying or dividing by powers of ten.