We've covered a lot of different types of device already—including input, output, and movement. This chapter delves into how these devices can be implemented in different ways and for different reasons. In this chapter, we'll take a look at the I2C and SPI protocols and their advantages and setbacks with Johnny-Five. We'll also take a look at how to add your own components to Johnny-Five, which gives us a good look into how these devices work and how you can contribute to the development of Johnny-Five! In this chapter, we will cover the following topics: