Temperature sensor circuit using Arduino

Introduction
Temperature sensor circuit can give us information about the temperature of any place(where we place the circuits) and we can control any thing which are function of temperature like Fan etc. The circuit gives us the information when the temperature of any place exceeds the set temperature.
Components Required
1. Arduino(i used Uno)
2. Temperature sensor(Thermistor)
3. Resistor about 2.2k
4. led or Motor
5. BC547 transistor