Functions are everywhere! It may sound a bit over the top, but functions are actually all over the place: all programmable things, all computer systems, mobile phones, apps, financial analyses, statistics, political analyses, price calculations, taxes, income calculations, earthquake warnings, landslide warnings, tsunami alerts, electronics, political forecasts, population growth forecasts, forecasts for sustainability—all forecasts in general! These are just a few examples where functions are used.

If you are going to study at a university, you are going to see functions. They are used in most subjects, including non-mathematical ones.

The reason is that functions say something about the connection or relationship between things. “What happens if $\dots$?” In this type of question, you can create mathematical models, and mathematical models are often functions. Given that you have a data set to be organized and analyzed, it is in this context you use functions. The function will then process the data set so that you can analyze the information.

Let’s consider Snapchat, Facebook or Instagram. All these apps are composed of functions. Some functions sort your friends list, other functions select filters. A third type of functions get used in the process of connecting your device to the internet. As you can see, functions make your life cooler, easier and more fun.