Function Parameters and Return

Function Parameters and Return

Functions can take inputs (parameters) and send back an output (return value).

Parameters

function greet(name) {
  console.log("Hello, " + name);
}
greet("Ada"); // Hello, Ada

The parameter name is a variable the function receives. When you call with an argument, the value flows in.

Multiple parameters

function add(a, b) {
  return a + b;
}

Return values

return sends a value back to whoever called the function:

function add(a, b) {
  return a + b;
}
let sum = add(3, 5); // sum is 8

The return statement

• Stops the function and sends the value back.
• A function without a return statement returns undefined.

Default parameters

function greet(name = "World") {
  console.log("Hello, " + name);
}
greet();      // Hello, World
greet("Ada"); // Hello, Ada

TL;DR

• Parameters are inputs a function receives.
• Arguments are the values you pass when calling.
• return sends a value back.
• Functions without return give undefined.
• Default parameters kick in when no value is passed.