What is a method?

A method is just a function that belongs to a class (or an object). It’s something the object can do.

Example 1 — A simple class with one method

JavaScript Example:

class Person {
  sayHello() {
    console.log("Hello!");
  }
}

const p = new Person();
p.sayHello(); // "Hello!"

• sayHello() is a method.
• You call it on the object with p.sayHello().

Example 2 — Method using this

JavaScript Example:

class Person {
  constructor(name) {
    this.name = name; // property
  }

  greet() {
    console.log(`Hi, I'm ${this.name}`);
  }
}

const anna = new Person("Anna");
anna.greet(); // "Hi, I'm Anna"

• In a constructor called with new, this refers to the new object being created.
  • In this example, new Person("Anna") creates a new object and assigns it to this inside the constructor.
• When a method is called on an instance of a class, this refers to that instance.
  • So, in the example, anna.greet() makes this refer to anna inside the greet() method.

Example 3 — Multiple methods

JavaScript Example:

class Counter {
  constructor() {
    this.value = 0;
  }

  increase() {
    this.value++;
  }

  show() {
    console.log(this.value);
  }
}

const c = new Counter();
c.increase();
c.show(); // 1

Each method adds some behavior to the class:

• increase() changes data
• show() displays it

In short:

Methods are functions inside a class that let objects do things or react to things.