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Data Type       Size (in bits)          Minimum Value                    Maximum Value
                   double       64                  4.9E –324                        1.7976931348623157E308
                   boolean      1                   True or False

                  Non-Primitive Data Types

                  The non-primitive data types are derived from primitive data types. The non-primitive data types
                  are also known as reference data types. Some of the examples of non-primitive data types are
                  class, interface, and array.

                  Literals

                  A literal denotes a constant value. Java has various types of literals. They are as follows:
                  •   Character Literal: A character literal is enclosed in single quotes and must have exactly one
                     character. For example, ‘a’ is a character literal that means the letter a.
                  •  String Literal: A string literal is always enclosed in double quotes. For example, “Hello World.”

                  •  Integer Literal: An integer literal is any number without a fraction. For example, 10 and 012

                  •   Floating-Point Literal: Any number with decimal points, like 3.12, is treated as a floating-point
                     literal.
                  •  Boolean Literal: Boolean literals can have either true or false values. They do not correspond
                     to 0 or 1 values as in C/C++.
                  Variables


                  Variables are the memory locations used to store values. When a variable is created, some space
                  is allocated for it in the memory. This memory space is referred to by the name that we give to
                  the variable. It is easy to create a variable in Java.
                  Declaring a Variable

                  In Java, a variable needs to be declared before use. Declaring a variable involves two steps: giving
                  the variable a name and stating what type of data is to be stored in the variable.

                  For example,
                         int age;
                         String name;
                         float temp;
                         double price;

                  Here, four variables named age, name, temp, and price are declared with the int, String, float, and
                  double data types, respectively.
                  Initialising a Variable

                  Intitialising means assigning a value to the variable at the time of declaration. We can initialise
                  variables in the following way:

                         int age = 30;
                         String name = "Nisha";



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