What is Objects And Classes OOPs Concept of JavaScript.

 // Defining Object  
var employee = {   
    // Propertise 
    empFirstName: "kajal", 
    empLastName: "singh", 
    // Methods 
    getFullName: function () { 
        return "employee name is " + this.empFirstName + " " + this.empLastName + "."; 
    }
} 
console.log(person.getFullName()); 

Output:- employee name is Kajal Singh.

// construtor to initialize variables 
function employee(first, last) { 
    this.employeeFirstName = first; 
    this.employeeLastName = last; 
} 
  
// with the prototype to define methods 
emplyee.prototype.getDetails = function () { 
    return "Employee name is " + this.employeeFirstName + " " + this.employeeLastName + "."; 
} 
  
  
var employeeName = new employee("Kajal","Singh"); 
console.log(employeeName.empFirstName); 
console.log(employeeName.getDetails()); 

Output:
kajal
Employee name is Kajal Singh.

// Define class using ES6 
class employee { 
    // Defining connstructor  
    // to initialize the property 
    
constructor(empFullName, employeeId) { 
        this.empFullName = empFullName; 
        this.employeeId = employeeId; 
    } 
  
    // Method returns employee details 
    getEmployeeDetails() { 
        return "Employee name is" + this.empFullName + ", Employee id is " + this.employeeId + "."; 
    } 
} 
  
// Creating an Employee Object  
var empObj = new employee("kajal", "15"); 
  
// Printing the Employee Details 
console.log(empObj.getEmployeeDetails()); 

Output:- Employee name is kajal, Employee id is 15.

// Defining class in a Traditional Way. 
function employeeDetail(empFullName, employeeId) { 
    this.empFullName = empFullName; 
    this.employeeId = employeeId; 
}; 
  
employeeDetail.prototype.getDetails = function(){ 
    return "Employee name = " + this.empFullName + ", Employee id = " + this.employeeId + "."; 
} 
  
var empObj = new Employee("kajal", "15"); 
console.log(empObj.getDetails()); 

Output:
Employee name = kajal , Employee id = 15.

Thanks & Regards,