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    The if Statement

                     The if statement is the simplest conditional statement. Here, a statement or a collection of statements
                     within the if block is executed only if a certain condition or expression evaluates to True. If the
                     condition evaluates to False, then the control of execution is passed to the next statement after the
                     if block. The syntax of the if statement is given below:

                     Syntax:

                     if (condition)                                                                              False
                                                                                             Test Expression
                     {

                           // When the condition is true then block of                               True
                         code to be executed.
                     }                                                                          Body of if

                                           Tech Fact
                        In JavaScript, the non-zero value is interpreted as               Statement just below if
                                true and 0 are interpreted as false.

                      Program 1: To check whether a given number is positive.

                     <!DOCTYPE HTML>

                     <HTML>
                     <HEAD>
                         <TITLE> if statement </TITLE>
                     </HEAD>

                     <BODY>
                     <SCRIPT>
                         var num = parseInt(prompt("Enter the number: "));
                         if(num > 0)

                         {
                           document.write("Entered Number is Positive");
                         }
                     </SCRIPT>

                     </BODY>
                     </HTML>

                                                                                     Conditional Statements in JavaScript  79

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