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•  boolean: The Boolean data type is used to store only two possible values: true or false. It specifies one bit of
                   information. The default value is “false”.

                        Type             Size                 Range             Default value           Example
                    byte         1 byte/8 bits        -128 to +127          0                     byte b = 10

                    short        2 bytes/16 bits      -32768 to +32767      0                     short s = 1234
                                                             31
                                                        31
                    int          4 bytes/32 bits      -2  to 2 -1           0                     int i = 123456
                    long         8 bytes/64 bits      -2  to 2 -1           0L                    double d = 123456L
                                                        63
                                                             63
                    float        4 bytes/32 bits      -3.4E+38 to 3.4E+38   0.0f                  float a = 10.67f
                    double       8 bytes/64 bits      -1.7E+308 to 1.7E+308  0.0 or 0.0d          double b = 1234.87674
                    char         2 bytes/16 bits      0 to 255              \u0000                char c = 'a'
                                                                                                  char d = '\u0041'

                    boolean      1 bit                true/false            false                 boolean a = true;
                 •  char: It stores character constants in the memory. The char data type is a single 16-bit Unicode character. It assumes
                   a size of 2 bytes, but basically it can hold only a single character because char stores Unicode character sets. It has
                   a minimum value of ‘\u0000’ (or 0) and a maximum value of ‘\uffff’ (65,535).

                                           Type           Size        Default value     Example
                                      char           2 bytes        \u0000          char c='a'
                                                                                    char d= '\u0041'
                   Java uses Unicode system, which includes ASCII code system and other characters from languages around the world.
                   To represent Unicode system, 8 bits is not enough to represent all characters, so Java uses 16 bits or 2 bytes for
                   characters.

                       Note: A word or a sentence includes more than one character, hence, it is called a String whose size
                       belongs to the number of characters together held. For example, if the word is “India”, then the size is 2
                       bytes × 5 characters = 10 bytes



                 Non-Primitive Data Types
                 Non-primitive data types are defined  by the user.  But  they are built  on  primitive data types,  i.e.,  they basically
                 concatenate two or more same or different types of primitive data types. For this reason, they are known as the
                 Derived data types. The different types of user-defined data types are String, class, array and interfaces. They are also
                 known as reference data types or composite data types or user-defined data types.

                                                              Non-Primitive




                                                      Class   Array  Interface  string

                 Now, we will discuss the non-primitive data types in detail.

                 Class
                 A class is a prototype created by the user from which the same type of objects are created. All the data members and
                 the methods of the class are common to all the objects have been created. For example,
                   class sum
                   {


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