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Comments
                 A comment is used to add notes in your code or to disable sections of code without deleting them. Comments are
                 ignored by the JavaScript interpreter. There are two types of comments in JavaScript: single line and multi-line. Single
                 line comments are added by using // and multi-line comments are added by using /* and */.
                 For example:

                   // alert("Hello"); Single line comment
                   /* a = 10;
                   b = 20; Multiline comment
                   */
                 Operators

                 Operators are special symbols that are used to perform mathematical, logical, and relational operations on values and
                 variables. The variables or values on which the operators work are called operands. Some commonly used operators in
                 JavaScript are arithmetic operators,  assignment operators or shorthand assignment operators, comparison operators,
                 logical operators, etc.
                 Arithmetic Operators
                 Arithmetic operators are used to perform mathematical operations on numbers in JavaScript. JavaScript provides the
                 following arithmetic operators:


                  Operator      Name                           Description                        Example       Output
                                                                                                (a = 11, b = 4)
                      +     Addition      Adds two operands.                                        a + b         15
                      –     Subtraction   Subtracts  the  operand  written  on  the  right-hand  side  of  the   a – b  7
                                          operator from the operand written on the left side.

                      *     Multiplication  Multiplies both operands.                               a * b         44
                      /     Division      Divides numerator by denominator.                         a / b         2.75

                     %      Modulus       Divides numerator by denominator and returns the remainder.  a % b       3
                     **     Exponent      Calculates  the  base  to  the  exponent  power,  that  is  base^   b**2  16
                                          exponent
                     ++     Increment     Used to increase the value of a variable by 1.            ++a           12

                     --     Decrement     Used to decrease the value of a variable by 1.             --a          10

                 Example: To calculate the square and cube of two numbers using JavaScript arithmetic operators.

                   <HTML>
                   <BODY>
                   <SCRIPT>
                   var num=5;
                   var sq=num**2;
                   var cube=num**3;
                   document.writeln("Square of "+num+"="+sq);
                   document.write("<br> <br>");
                   document.write("Cube of "+num+"="+cube);
                   </SCRIPT>

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