Methods are functions that describe the class in some way. Real Students can do actions like studying, sleeping, talking, etc, so we can define it as methods of the class:

class Student{
  name;
  university;
  age;
  gpa;
  sleep(){
    console.log('I am sleeping right now!');
  }
}

s = new Student();
s.sleep();

We added method `sleep()`, which prints a message.

This method is trivial, but in general, methods can also be used for:

- Changing some attribute’s value
- Extracting some attribute’s value
- Calling other methods inside
- Printing something to the console etc.

Let’s demonstrate it and add the method `happyBirthday()`. This method increases age of the student and prints some info about it:

class Student{
  name;
  university;
  age;
  gpa;
  sleep(){
    console.log('I am sleeping right now!');
  }
  happyBirthday(){
    this.age += 1;
    console.log('Today is my birthday!');
  }
}

s = new Student();
s.happyBirthday();

// method of the class
happyBirthday(newAge){
  this.age = newAge;
  console.log('Today is my birthday!');
}

> Actually you already met attributes and methods in other objects. For example, `length` is a attribute of some object of the class `array`. In the `console.log()`, `console` is a class to write some data to the stream, and `log()` is a method, that prints your data (like 'hello world') to the stream.

Every programmer should be familiar with OOP principles. If basic JavaScript syntax doesn't scare you and you want to develop your projects, start learning OOP right now!

Object is the first 'O' in Object-Oriented Programming. Let's create one.

The encapsulation is next OOP principle, that help to control and validate the behavior of the class and objects.

Learn how to detect if the field should be static.

Learn why some classes are parents of other classes.

Class Methods

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