Standard Input ( cin )

   >>> The standard input device is usually the keyboard.

   >>> Cout is used in conjunction with the >>. The operator  >> is known as extraction or get-from operator. The operator must be followed by the variable that will store the data that is going to be extracted from the stream.

   >>> Cin is an object, predefined in C++ to correspond to the standard input stream. This stream represents data coming from the keyboard.

   >>> The >> takes the value from the stream object on its left $ places in the variable on its right.

   >>> For example :

                                int age;
                                cind >> age;

   >>> The first statement declares a variable of type int called age and the second one waits for an input from cin ( the keyboard) in order to store it in this integer variable.

   >>> Cin is an object, predefined in C++ to correspond to the standard input stream. This stream represents data coming from the keyboard.

   >>> The >> takes the value from the stream object on its left $ places in the variable on its right.

   >>> For example:

                              int age;
                              cin >> age;

   >>> The first statement declares a variable of type int called age, and the second one waits for an inputs from cin (the keyboard) in order to store it in this integer variable.

   >>> Cin can only process the input from the keyboard once the RETURN key has been pressed. Therefore, even if you request a single character the extraction from cin will not process the input until the used presses RETURN after the character has been introduced.

   >>> You must always consider the type of the variable that you are using as a container with cin  extractions. If you request an integer you will get an integer, if you request a character you will get a character and if you request a string of characters you will get a string of characters.

   >>> You can also use cin to request more than one datum input from the user:

                           cin >> a >> b;

                     is equivalent to :

                            cin >> a;
                            cin >> b;

   >>> In both cases the user must give two data, one for variable a and another one for variable b that may be separated by any valid blank separator: a space, a tab character or a newline.