어떤 코드를 캡슐화해서, 실행을 여러번 할 수 있게 해줌
function 함수이름() {
함수에 들어갈 내용
}
ex)
function sayHello(){
console.log("Hello!");
}
sayHello(); //Hello
sayHello(); //Hello
sayHello(); //Hello
function plus(firstNumber, secondNumber) {
console.log(firstNumber + secondNumber);
}
function divide(a, b){
console.log(a / b);
}
plus(60, 8); //68
divide(98, 20) //4.9
const player = {
name: "hyunsu",
sayHello: function(otherPersonName){
console.log("hello! " + otherPersonName + " nice to meet you!");
}
};
player.sayHello("Hyun"); //hello! Hyun nice to meet you!