ES6 uses class to achieve inheritance

class Animal {
    
    
    constructor(name, age) {
    
    
        this.name = name;
        this.age = age
    }
    showName() {
    
    
        console.log(this.name);
    }
}

class Cat extends Animal {
    
    
    constructor(name, age, sex) {
    
    
        super(name, age);
        this.sex = sex;
    }
}

let cat = new Cat('jake', 18, 'female');
cat.showName();	// jake