# Temperature

Temperature
Temperature is how hot or cold a thing is. A thermometer can be used to find out the temperature. Temperature is often measured in degrees Celsius (°C). In the USA, degrees Fahrenheit (°F) are more often used. Scientists use kelvins (K) to measure temperature.
Water freezes at a temperature of 0 °C, 32 °F, or 273.15 K.
The internal temperature, so-called core body temperature, of the human body is close to 37 °C or 98 °F.
Water boils at 100 °C, 212 °F, or 373.15 K.
The coldest temperature is absolute zero. Absolute zero is 0 K or -273.15 °C.
Temperature is not the same as heat. Temperature is how hot or cold a thing is. Heat is how much energy is in the small and fast movements (vibration) of its molecules.
The more heat a thing has the more temperature it has. But it is possible to have a cold thing (less temperature) have more heat than a hot thing (more temperature). This is because the cold thing has more heat capacity and so takes more heat to make it hot. For example, two kilograms of water at 20 °C has twice as much heat as one kilogram of water at 20 °C. In fact, two kilograms of water at 10 °C has more heat than one kilogram of water at 20 °C. Also, the "same" amount of different substances can have different heat capacities. For example, a kilogram of water has more heat capacity than a kilogram of steel.
Temperature says whether heat will move from one thing to another. Unless some work is done, heat moves only from hot things to cold things. To a scientist this is the most important thing about temperature.
Temperature is also an important climatic element. It shows the amount of heat energy in the air. Isotherm maps are used to show the distribution pattern of temperature in an area. Temperature is different during different periods, seasons and in different places. It is affected by