NTC is short for Negative Temperate Coefficient.
The main characteristic of a NTC thermistor is the value for resistance is varied with temperature change. The resistance will decrease when the temperature rises, and increase when the temperature drops.
For example, a thermistors resistance is 50kΩ at 25℃. If the temperature was increased to 50℃, the resistance would lower to 40kΩ. These values are just an example. Thermistors come in a wide variety of resistance and styles.
A great example to better understand the function of a thermistor would be a coffee maker. When the coffee is done, the coffee maker keeps the coffee warm automatically. When the machine reaches optimum temperature, the resistance of the thermistor in the coffee machine will decrease. With current changing, the machine will switch from a heating state to a warming state automatically.
