Variables and functions
You can define variables by using the var, let and const keywords. You can also use the keyword “global” to declare them outside the function scope.
Variables are also declared inside a function by using the arrow function keyword. These shorten the syntax for writing functions and make them easy to write.
The most popular operator is multiply, which divides a number by another. It can be used to calculate a product’s price, for example.
Moreover, you should also know about function closures and arrow functions.
Closures are used to capture non-local variables by reference, so that they can be reused elsewhere in your program. They’re very helpful when you have multiple nested function calls or if you need to refer to non-local variables from other functions. They also help you to keep your code clean and concise.