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4.4 REASON FOR CHOOSING JAVASCRIPT
                 HTML  is  capable  of  producing  pages  that  are  more  or
                 less  static.  The  view  doesn’t  alter  much  once  you  load          Development
                 them up until you click a link to go to a new page. Adding                    of
                 JavaScript to your code, on the other hand, allows you                    Mul	media
                                                                                           Applica	ons
                 to alter the appearance of the page in a variety of ways,
                 like changing the text, changing the colours, changing the
                 options accessible in a drop-down list, and much more.

                 The majority of JavaScript operations are instantaneous.   Suppliments     Uses of            Dynamic
                                                                         Client and
                 In reality, JavaScript is frequently utilised to accomplish   Sever Side  JavaScript           Page
                 tasks that would otherwise slow down the server, such   Processing                            Crea	on
                 as form validation. This work load allocation to client-side
                 services considerably speeds up the process.
                 JavaScript has various uses/applications as shown below:

                 Ð ÐDevelopment of Multimedia Applications: JavaScript                     Valida	on of
                                                                                           User Input
                   can be used by the user to include multimedia elements
                   like images, audio, video, animations, etc. within the
                   web  pages.  You  can  show,  hide,  modify,  resize,  and
                   create picture rollovers with JavaScript. By adding scrolling text to the status bar, multimedia applications can
                   become more engaging.

                 Ð ÐDynamic Page Creation: JavaScript allows the users to change the elements of the web pages dynamically.
                 Ð ÐValidation of User Input: This is one of the primary applications of JavaScript, which allows users to validate input
                   entered into various types of fields such as textboxes.

                 Ð ÐSupplements Client and Sever Side Processing: JavaScript can be processed on the client side as well as the server
                   side.

                   4.5 ROLE OF JAVASCRIPT IN WEB DEVELOPMENT

                 HTML Language is used to create web documents or web pages. JavaScript is embedded in the HTML code. The
                 <script> tag informs the browser about JavaScript code in the HTML code. A complete web page can be visualized as
                 three separate layers which allows the designer to concentrate on a particular part and programmer can work on the
                 code in JavaScript application. Here is a brief description of these layers.

                 Structure

                 This is the part of the website that users see, and it consists of text, images, and links that allow the user to navigate
                 through the various pages or the entire website. HTML tags are used to specify the document’s structure. The browser
                 perceives the display as a tree-like structure.

                 Style

                 This layer describes the appearance of the document. Setting the font colour, background image, border, and alignment,
                 for example, all fall under this layer. These operations can be carried out utilising the page’s HTML elements or the
                 cascading style sheets (CSS). When we have to make modifications in multiple places on a page or pages, the former is
                 more difficult, whereas the same CSS can be used on thousands of pages.

                 Behaviour

                 This layer outlines the actions that the page can execute. A user can interact with a web page by pressing specific keys,
                 rolling or clicking the mouse, filling out forms, and so on. JavaScript makes it simple by processing events that occur on
                 the web page and displaying the appropriate answer.

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