Parameters, Arguments & Default Arguments

Functions can receive data through parameters. Parameters act as placeholders for values that you'll provide when calling the function. 

function greetByName(name) {

    console.log("Hello, " + name + "!");

}

greetByName("Alice"); // Output: Hello, Alice!

greetByName("Bob");   // Output: Hello, Bob!

In this example, the greetByName function takes a name parameter, and you provide the actual value when calling the function.

Default Arguments 

Default arguments are a feature in JavaScript functions that allow you to assign default values to parameters. 

function greet(name, greeting = "Hello") {

    console.log(greeting + ", " + name + "!");

}

greet("Alice"); // Output: Hello, Alice!

greet("Bob", "Hi"); // Output: Hi, Bob!