Classes in javascript

Classes in JavaScript are syntactic sugar over the prototypal inheritance system. The class keyword lets you define a constructor and methods in a concise way, while under the hood it still uses prototypes. Use extends and super for inheritance.

Example

class Person {
  constructor(name) {
    this.name = name;
  }
  greet() {
    return `Hi, I am ${this.name}`;
  }
}

class Developer extends Person {
  constructor(name, stack) {
    super(name);
    this.stack = stack;
  }
  describe() {
    return `${this.name} codes in ${this.stack}`;
  }
}

const dev = new Developer("Punam", "MERN");
dev.greet();    // "Hi, I am Punam"
dev.describe(); // "Punam codes in MERN"

The Developer class extends Person, reusing the constructor via super and adding its own behavior; methods are shared via the prototype.

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