JavaScript for Kids

Chapter 8. Functions

A function is a way to bundle code so that it can be reused. Functions allow us to run the same piece of code from multiple places in a program without having to copy and paste the code repeatedly. Also, by hiding long bits of code in a function and giving it an easy-to-understand name, you’ll be better able to plan out your code because you can focus on organizing your functions rather than all of the little code details that make them up. Splitting up your code into smaller, more manageable pieces allows you to see the bigger picture and think about how your programs are structured at a higher level.

You’ll find functions really useful when you need to repeatedly perform a calculation or action throughout a program. Earlier ...