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2.4 JAVASCRIPT DATA TYPES

              In JavaScript, a data type defines the kind of value a variable can hold. data types are categorized into two
              main types: primitive and non-primitive (or reference) data types.

                                                                       Data Type




                                          Primitive Datatypes                             Non-Primitive Datatypes



                  Strings   Numbers: Integers   Boolean   Undefined      Null        Objects      Array      Functions
                              Floating-Point,
                            Exponential, NaN,
                                 Infinity


              Primitive Data Types

              Primitive data  types are the basic building blocks of data  in JavaScript.  They are immutable  (cannot  be
              changed) and are stored directly in the variable. The primitive data types in JavaScript are:
                String: Represents a sequence of characters enclosed in single quotes, double quotes, or backticks.

                 For example:

                var sentence1 = "Hello, this is sentence one! "; //primitive type or string literal
                var sentence2 = 'This is a string sentence two.';
                var sentence3 = 'She said, "This is sentence three inside quotes."';
                Number: A number data type can be represented in various forms such as integers, floating-point values,
                 exponential values, NaN, and Infinity. Here's how they are used:
                   Integer Value: An integer value is a whole number without any fractional or decimal part. It can be
                    positive, negative, or zero.
                    For example:
                    var a = 250; // an integer

                   Floating-Point Value: A floating-point value is a number that includes a decimal point, allowing for
                    representation of real numbers with fractional parts.
                    For example:

                   var b = 25.5; // a number with a decimal
                   Exponential Value: An exponential value represents a number in the form of a base and an exponent,
                    written as base e^exponent.
                    For example:
                    var c = 20e5; // an exponential value, which evaluates to 20 * 200000
                   NaN (Not a Number): This occurs when an operation involves non-numeric values.

                    'hi' * 3; // results in NaN
                   Infinity: JavaScript includes special numeric values. When a number is divided by 0, the result is Infinity.
                    For example:
                    var d = 3/0 // results in Infinity


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