In this first chapter, we built a simple alarm based on Arduino with only a few components.

There are several ways to go further and improve this project. You can add more functions to the project just by adding more lines to the code. For example, you can add a timer so that the alarm only goes off after a given amount of time, or you can build a mode where a push of the button actually activates or deactivates the alarm mode.

In the next chapter, we are going to build another project that is very useful for secret agents: an audio recording device based on Arduino!