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•  Public: Methods and variables when declared public can be used within a class as well as outside the class. If the
                     access specifier is not mentioned, then by default it is taken as public.
                     E.g., public int a, b, s=0;
                   •  Private:  Data members and variables declared as private can be accessed only from within the scope of the class.
                     E.g., private int radius, area, perimeter;
                   •  Protected: When we declare data members and methods as protected, then the members can not only be
                     accessed from the same class but also from the inherited class.
                     E.g., protected int length, breadth;
                 b. Class: It is a reserved word that is used to declare a class.
                 c.  Name of the class: It is used to give a name to define the class so that it can be easily referred to when required.
                 d. Data Members: They are the variables described within a class and can be used to store values whenever required.
                 e. Member Methods: The defined methods in a class are termed Member Methods. These methods have some stored
                   values which are used as global variables and these variables are also used to perform some jobs.

                 Apart from the above mentioned, there are two parts of a class which are as follows:
                 a. External Wrapper: The whole class is encapsulated in a bracket. It contains the reserved word “class” and the class
                   name.
                 b. Internal Wrapper: Whatever is contained in the braces after the class name, is the Internal Wrapper. It contains the
                   instance variable, class variable, local variable, constructor and member methods.
                   •  Instance Variable: It is a non-static data member that is  created whenever any object is generated. All instance
                     variables are accessed by preceding it with the object name.
                     For example,
                        char ch;
                        short s;
                   •  Class Variable: It is also known as a static data member which is capable of creating only one copy for all the
                     objects of the class. Thus, there would be only one copy of the variable per class, no matter the number of objects
                     that may be created from it.
                     For example,
                        static int a;
                        static double b;
                     Differences between ordinary and static data members are as follows:

                                   Ordinary Data Members                           Static Data Members
                       All  objects  created  have  individual  data  members  Only  one  copy  of  the  data  members  is  used  by  all  the
                       assigned to them.                            objects created.
                       Any change in the value stored in a data member will  Any change made in a static data member through an object
                       affect only the respective object.           will affect the common data members of all the  objects.
                     Let us see an example given below:

                        class counter
                        {
                            static int increase=0;
                            static void incre()
                            {
                                  increase++;
                            }
                            void display()
                            {
                                  System.out.println("Counter : "+ increase);
                            }
                            public static void main()


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