private void button1_Click
            (object sender, EventArgs e)
        {
            //Arraylist - Arraylist accept values as object
            //So i can give any type of data in to that.
            //Here in this eg: an arraylist object accepting 
            //values like String,int,decimal, char and a custom object

            Employee emp = new Employee("2", "Litson");
            ArrayList arr = new ArrayList();
            arr.Add("Sabu");
            arr.Add(234);
            arr.Add(45.236);
            arr.Add(emp);
            arr.Add('s');
            //This process is known as boxing

            //To get inserted vales from arraylist we have to specify the index.
            //So it will return that values as object.
            //we have to cast that value from object to its original type.

            String name = (String)arr[0];
            int num = (int)arr[1];
            decimal dec = (decimal)arr[2];
            Employee em = (Employee)arr[3];
            char c = (char)arr[4];
            //This process that is converting from object to its original type is known as unboxing
            //------------------------------------------------------------------------------------
            //Generic List
            //List<>

            //Main advantage of Generic List is we can specify the type of data we are going to insert in to
            //List. So that we can avoid boxing and unboxing
            //Eg:
            List<String> strLst = new List<string>();
            strLst.Add("Sabu");//Here List accepting values as String only
            strLst.Add("Litson");
            strLst.Add("Sabu");
            strLst.Add("Sabu");

            List<int> intLst = new List<int>();
            intLst.Add(12);//Here List accepting values as int only
            intLst.Add(14);
            intLst.Add(89);
            intLst.Add(34);

            List<decimal> decLst = new List<decimal>();
            decLst.Add(2.5M);//Here List accepting values as deciaml only
            decLst.Add(14.4587m);
            decLst.Add(89.258m);
            decLst.Add(34.159m);

            List<Employee> empLst = new List<Employee>();
            empLst.Add(new Employee("1", "Sabu"));//Here List accepting Employee Objects only
            empLst.Add(new Employee("2", "Mahesh"));
            empLst.Add(new Employee("3", "Sajith"));
            empLst.Add(new Employee("4", "Binu"));


            //To get values from Generic List
            String nme = strLst[0]; //No need of casting
            int nm = intLst[0];
            Decimal decVal = decLst[0];
            Employee empVal = empLst[0];
        }