Fritzing

Required Components  Arduino UNO board (buy from here arduino ) Temperature sensor IC LM35( buy from here LM35 sensor ) DC Fan resistor 1* 1K 16*2 LCD Display Power supply   Diode(1N4007)

In this application, we use an arduino board to control the speed of the fan and a 16*2 LCD display to display the status of the fan. Here we use a diode in parallel with FAN to prevent it from the damage and a 9V battery to provide power to the fan.