Circuit 1 - Blink an Led
In the video shown it outputs the blinking yellow led light
In the code there is 1 second delay that blinks the led in a loop.
Circuit 2 - Potentiometer
In the video shown the more you turn the arrow in one direction the faster the LED blinks.
Circuit 3 - RGB LED
In the video shown the LED changes color every second
Circuit 4 - Multiple LEDs
By connecting EIGHT LEDS AT ONCE. Creating various lighting sequences.
Circuit 5 - Push Buttons
In this circuit, we'll be looking at one of the most common and simple inputs — a push button. The way a push button works with Arduino is that when the button is pushed, the voltage goes LOW
Circuit 6 - Photo resistor
A photo resistor, which changes resistance based on how much light the sensor receives. Since the Arduino can't directly interpret resistance.