Temperature is how hot or cold a thing is. Our bodies can feel the difference between something which is hot and something which is cold. To measure temperature more accurately, a thermometer can be used. Thermometers use a temperature scale to record how hot or cold something is. The scale most often used is in degrees Celsius (°C), sometimes called centigrade. In the USA, degrees Fahrenheit (°F) are more often used, while scientists mostly use kelvins (K) to measure temperature because it never goes below zero.
Can you figure out this picture? The red is really hot. The purple is really cold. How do Celsius and Fahrenheit compare? Look at the numbers above. Ten degrees Celsius is about how much in Fahrenheit? (answer: 50 degrees)
A thermometer is an instrument for measuring or showing temperature (how hot or cold something is). One type of thermometer is a narrow, concealed glass tube containing mercury or alcohol, which extends along the tube as it expands. Another type is a digital thermometer, which uses electronics to measure temperature.