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•  double: The double data type is a double-precision 64-bit IEEE 754* floating point or equivalent to 8 bytes. For
                 decimal values, this data type is generally the default choice. The double data type can store fractional numbers
                 from 1.7e-308 to 1.7e+308, i.e., values up to 16 decimal digits. Note that you should end the value with a “d”. The
                 default value is 0.0d.
                For example: double a = 36.14264d, double b = 748.64789d
                Let us summarise the above details in the table given below.

                           Type             Size           Default      Range of values that      Format
                                                           value           can be stored

                      Float           4 bytes/32 bits       0.0f        3.4e-038 to 3.4e+038  float a=10.67f
                      double          8 bytes/64 bits    0.0 or 0.0d    1.7e-308 to 1.7e+308  double b=1234.87674

                      Note: The IEEE Standard for Floating-Point Arithmetic (IEEE 754) is a technical standard for floating-point
                      arithmetic established in 1985 by the Institute of Electrical and Electronics Engineers (IEEE).


              Character Type
              Character data type can hold character data. It is represented by char which is discussed below.

              •  char: The char data type stores the 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). The default value
                 is ‘\u0000’.
                For example: char ch = ‘x’

                The above description is tabulated below.
                           Type             Size           Default      Range of values that      Format
                                                           value           can be stored
                      Char            2 bytes\16 bits      \u0000      ‘\u0000’ (or 0) to    char c = ‘a’
                                                                       ‘\uffff’ (or 65,535)  char d= ‘\u0041’


              Boolean Type
              Boolean data type can take only two possible values. It is represented by a boolean which is discussed below.

              •  boolean: The Boolean data type is used to store only two possible values: true and false. This data type is used for
                 simple flags that track true/false conditions. The Boolean data type specifies one bit of information. The default
                 value is false.

                For example: boolean a = false
                The specifications of the boolean data type are illustrated below.
                           Type             Size        Default value   Range of values that      Format
                                                                           can be stored
                      Boolean         1-bit           False            true Or false       boolean a = true;


                      Note: 1. Integer and Float data types are numeric data types.
                            2. Character and Boolean data types are non-numeric data types.

              5.1.3 Non-Primitive Data Types
              Non-primitive data types are also called Reference Data Types or Composite Data types. They contain a memory
              address of a variable or  value because the reference types won’t store the value of the variable directly in memory.


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