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WEB SCRIPTING—JAVASCRIPT                                                       3












                 JavaScript  is essentially an interpreted programming language.  It was initially built into web
                 browsers so that client-side scripts could communicate dynamically, control the browser, interact
                 with the user, and modify the contents of documents. These days, both the development of
                 desktop programmes and video games makes extensive use of JavaScript.

                 Brendan Eich at Netscape created JavaScript in 1995, and it was originally made available with
                 Netscape 2 in early 1996. To capitalise on the success of Sun Microsystem’s Java language, it was
                 originally known as LiveScript but was renamed as JavaScript. JavaScript’s use extends beyond
                 web pages to include desktop widgets, site-specific browsers, PDF documents, and other useful
                 applications.

                   3.1 REVIEW OF JAVASCRIPT

                 JavaScript is an object-oriented, cross-platform scripting language. Although it is not usable as a
                 standalone language, it can be easily embedded with other software and hardware, such as web
                 browsers. JavaScript can link to the objects of its environment inside a host environment and grant
                 programmatic control over those items.
                 Along with a basic collection of language  components like operators, control structures, and
                 statements, core JavaScript also includes a core set of objects including Array, Date, and Math. By
                 adding more objects, core JavaScript can be enhanced for a number of uses:
                   Client-side: By providing objects to manage a browser’s Document Object Model (whether
                    it is Navigator or another web browser), JavaScript enhances the core language (DOM). An
                    application can, for instance, add items to an HTML form and react to user actions like mouse
                    clicks, form input, and page navigation using client-side extensions.

                   Server-side: By providing objects necessary for executing JavaScript on a server, JavaScript
                    expands the language’s base syntax. Server-side extensions, for instance, enable an application
                    to interact with a relational database, maintain information across application calls, or handle
                    file operations on a server.
                 The standardised version of JavaScript, known as ECMAScript, was created as a result of the effort
                 that followed Netscape’s announcement in November 1996 that it had submitted JavaScript to the
                 European Computer Manufacturers Association (ECMA) for consideration as an industry standard.
                 ECMA is a global organisation for information and communication system standards.







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