Summary

In this chapter, we have covered functions. Functions are a great JavaScript building block that we can use to reuse lines of code. We can give our functions parameters, so that we can change the code depending on the arguments a function gets invoked with. Functions can return a result; we do so using the return keyword. And we can use return at the place where we call a function. We can store the result in a variable or use it in another function, for example.

We then met with variable scopes. The scope entails the places from where variables are accessible. Default let and const variables can be accessed inside the block where they're defined (and the inner blocks of that block) and var is just accessible from the line where it was defined.

We can also use recursive functions to elegantly solve problems that can be solved recursively by nature, such as calculating the factorial. Nested functions were the next topic we studied. They are not a big deal,...