This ends the introduction to the Arduino programming language. You can refer to the Arduino quick reference pages for additional information about the Arduino programming language.
You can find the reference pages here: https://www.arduino.cc/reference/en/. On this page, you will find links to information about the built-in Arduino functions and variables. That are also links to information about the operators and other Arduino language elements.
Don't worry if you do not feel comfortable writing your own Arduino programs right now because we will be writing a lot of code in the remaining chapters of this book, and by the end you should feel comfortable writing your own Arduino applications.