use of "this" keyword

Imagine this situation

public class Person
    {
        public string FirstName { get; set; }
        public string LastName { get; set; }
        public int identifier { get; set; }
        //The overloaded constructor
        public Person(string FirstName,string LasName, int identifier)
        {
             //TO DO initialize the Person members within the constructor scope
        }
    }
OK, how to distiguish between the FirstName(member of the class instance) and FirstName(argument in the constructor), the world this enables the compiler distiguish between the two element inspite of the same name, same thing for the others I mean LastName and identifier so I write

public class Person
    {
        public string FirstName { get; set; }
        public string LastName { get; set; }
        public int identifier { get; set; }
        //The overloaded constructor
        public Person(string FirstName,string LasName, int identifier)
        {
            //Class member =  Constructor arguement
            this.FirstName = FirstName;
            this.LastName = LastName;
            this.identifier = identifier;
        }
    }
Ok you tell me I can change the arguement nomination firstName or fn or fname and avoid the conflict in the names I tell you the problem will persist you tell me how? I tell you
the class is used to derive several instances
            Person me = new Person("Bejaoui", "Bechir", 1);
            Person you = new Person("anveshreddy", "amaravadi", 2);
            Person vijaya = new Person("Vijaya","Kadyiala",3);
Ok the problem is how the compiler can differenciate between the FirstName of me, the FirstName of you and the FirstName of Vijaya, is by using the this Keyword who serves as a pointer that point to the targeted FirstName among the rest of the FirstNames of the other instances
       
 

Hi

The this keyword refers to the current instance of the class. Static member functions do not have a this pointer. The this keyword can be used to access members from within constructors, instance methods, and instance accessors.

The following are common uses of this:

• To qualify members hidden by similar names, for example:
  public Employee(string name, string alias)
  {
     this.name = name;
     this.alias = alias;
  }
• To pass an object as a parameter to other methods, for example:

      CalcTax(this);

Check out the below link:

http://msdn.microsoft.com/en-us/library/dk1507sz%28VS.71%29.aspx

Thanks -- Vijaya Kadiyala