Functions are created/ defined then they are called.
Defining a function:
// Function definition
function calculateBill() {
// this is the function body
console.log('running calculateBill');
}
Calling a function:
// Function call or run
calculateBill(); // running calculateBill (returns undefined)
Variables created inside a function are not available outside the function. e.g. total
above.
It is a temporary variable. After running of the function is complete, the variable is cleaned up or garbage-collected.
Returning value from function:
function calculateBill() {
const total = 100 * 1.13;
return total; // total is returned
}
calculateBill(); // returns 112.999999999
Capturing returned value from a function into a variable:
const myTotal = calculateBill();
(myTotal will have value 112.999999999)