When I log this to the console it shows up as undefined. However, when I remove the braces in the function it logs the desired result. I'm confused -- aren't we always supposed to include curly braces in a function? Thank you all.

const shoutGreetings = arr => {
  arr.map(word => word.toUpperCase() + '!')
};

const greetings = ['hello', 'hi', 'heya', 'oi', 'hey', 'yo'];
console.log(shoutGreetings(greetings))