A person’s body temperature is measured using an instrument called a thermometer. The word “thermometer” comes from the Greek word therme (heat) and the French word metre (measure).

There are two general types of thermometers–the glass thermometer and the electric thermometer. The glass thermometer is easier to carry than the electric thermometer and is cheaper to replace. The electric thermometer measures temperatures faster and does not have to be sterilized after each use as does the glass thermometer.