A function is a reusable block of code that groups together a sequence of statements to perform a specific task. One way to create a function is by using a function declaration. Just like how a variable declaration binds a value to a variable name, a function declaration binds a function to a name, or an identifier. A function declaration does not ask the code inside the function body to run, it just declares the existence of the function. The code inside a function body runs, or executes, only when the function is called...

Introduction When we say the word “bake”, it calls to mind a familiar subroutine— preheating an oven, putting something into an oven for a set amount of time, and finally removing it. This allows us to abstract away a lot of the details and communicate key concepts more concisely. Higher-order functions are functions that accept other functions as arguments and/or return functions as output. This enables us to build abstractions on other abstractions, just like “We hosted a birthday party” is an abstraction that may build on the abstraction “We made a cake...