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Info Hub: Introduction to JavaScript






                 In the previous classes, we have learnt to create web pages using HTML. HTML uses many tags
                 to tell the browser how to display the content on web browsers. The web pages we have learnt to

                 create were static in nature which were not interactive. We need to use another scripting language
                 along with HTML to make web pages interactive and dynamic in nature. JavaScript is one of such
                 types of scripting languages.

                 JavaScript—A Scripting Language


                 JavaScript, often abbreviated as JS, is a client-side scripting language used for enhancing users’
                 interaction with the web page by making web pages dynamic. The meaning of client-side scripting
                 language is that the code written in JavaScript is interpreted by the web browser on which the web
                 page is running. With the help of JavaScript, we can add different types of functionalities in our web
                 pages like taking input from the user, validating the user input, displaying pop-up boxes, etc.

                 Alongside HTML5 and CSS, JavaScript is one of the core languages of the World Wide Web (WWW).
                 It was developed by Brendan Eich, a Netscape Communications Corporation programmer, in 1995.
                 He takes only ten days to develop the language.


                 Features of JavaScript

                 Some of the important features of JavaScript are as follows:

                   It is used in both client-side and server-side applications.

                   It is platform independent; hence, it runs on many operating systems.

                   It is used with HTML code and run on web browsers.
                   It is a case-sensitive and interpreted language.

                   It is used to validate user input for errors.

                 Using JavaScript

                 JavaScript cannot run on its own because it is a scripting language, and hence, needs to be embedded
                 within an HTML code.


                 In HTML5, we can use JavaScript in two ways: internally and externally.

                 Internal JavaScript

                 When JavaScript code is written within the HTML web page then it is called internal JavaScript.
                 We use the <SCRIPT> and </SCRIPT> tags to place the JavaScript codes either in the <HEAD> or
                 <BODY> tag of the HTML5 document.




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