‘Higher-order functions’ is a fancy term for functions that take other functions as arguments or that return functions. Very powerful!

Ordinarily with JavaScript, you can change pretty much any variable you want. Any variable you declare can be reassigned to any other value, unless you use the const keyword.

JavaScript Typing Unlike strongly typed programming languages such as C#, JavaScript is loosely typed and allows you to assign any data type to a variable without giving the variable a specific type.