The photoresistor or LDR is a resistor that varies its value according to the light falling on it and therefore it can be used with Arduino to create innovative and more complex projects.

Connect the LED and LDR to Arduino as shown on the image.

List of components:

U1 1 Arduino Uno R3
R1 1 1 kΩ Resistor
R2 1 220 Ω Resistor
R3 1 Photoresistor
D1 1 Orange LED