Day 5: Functions Part 1

Lesson 3: Input, No Return

Functions that take no input are pretty limiting. Let's expand our function to take an input so it can be a bit more personalized.

<h1>Hello World<h1>

function sayHello(name) {
  console.log("Hello " + name);
}

sayHello("Coder");

When we declare the function we put name in the ( ) to say "hey, this function takes an argument called name). You can then access/use that argument inside the function by it's name.

When we call the function, we put what we want to be passed into the function inside the ( ). We pass in a string "Coder" and that gets logged inside the function.

You can pass in a variable as well, of course.

<h1>Hello World<h1>

function sayHello(name) {
  console.log("Hello " + name);
}

const usersName = "Cool Coder";

sayHello(usersName);

This also highlights something important. What you call your argument when declaring the function (we chose name) doesn't mean you have to use that same variable name on the outside (see how we chose usersName?).

JavaScript function arguments are positional. Which will be important in a couple of lessons time.

In the meantime, let's get something back from our function.