You have now completed the basic introduction to the world of Arduino. In short, you have successfully set up your Arduino and have written your first code. You also learned how to modify the existing code to create something new, making it more suitable for your specific needs. This methodology will be applied repeatedly while programming, because almost all the code available is open source and it saves time and energy.

In the next chapter, we will look into sensors and displays. You will build a digital ruler that you can use to measure short distances. It will consist of an ultrasound sensor to compute distance and a small LCD screen to display it. Additionally, we will look at safely powering the Arduino board using a battery so that you are not dependent on your computer for USB power every time.