function sayHello() {
    console.log('Hello!');
}

sayHello();

/* function with parameter */
function output(text) {
    console.log(text);
}

output('Hello!');

output('Hello!', 'Other text');

output();

/* function using the return statement */
function sum(num1, num2) {
    return num1 + num2;
}

var result = sum(1,2);
output(result);