Javascript An Introduction

by Rao Muhammad Aftab Fri Sep 02, 2011 9:07 am

JavaScript is a prototype-based, object-oriented scripting language that is dynamic, weakly typed and has first-class functions. It is also considered a functional programming language like Scheme and OCaml because it has closures and supports higher-order functions.

JavaScript is an implementation of the ECMAScript language standard and is primarily used in the form of client-side JavaScript, implemented as part of a web browser in order to provide enhanced user interfaces and dynamic websites. This enables programmatic access to computational objects within a host environment.

JavaScript's use in applications outside web pagesâ€”for example in PDF documents, site-specific browsers, and desktop widgetsâ€”is also significant. Newer and faster JavaScript VMs and frameworks built upon them (notably Node.js) have also increased the popularity of JavaScript for server-side web apps.

JavaScript uses syntax influenced by that of C. JavaScript copies many names and naming conventions from Java, but the two languages are otherwise unrelated and have very different semantics. The key design principles within JavaScript are taken from the Self and Scheme programming languages.
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"JavaScript" is a trademark of Oracle Corporation. It is used under license for technology invented and implemented by Netscape Communications and current entities such as the Mozilla Foundation.

Four feathers of J
1. Browser support

To access flash content, you need to install flash plugin in your browser. But to use javascript, you don't have to use any plugin at all. This is because all browsers have accepted javascript as a scripting language for them and provides integrated support for it. All you need to do is to handle some of the tasks that are dependent on DOM (Document Object Model) of different browsers properly.

2. Can be used on client side as well as on server side

As javascript has access to Document object model of browser, you can actually change the structure of web pages at runtime. Due to this, javascript can be used to add different effects to webpages. On the other hand, javascript could be used on the server side as well. For example, in Alfresco which is a popular open source enterprise content management system, javascript is used in creating webscripts. This makes adding custom tasks to alfresco quite simple.

3. Functional programming language

In javascript, function could be assigned to variables just like any other data types. Not only that, but a function can accept another function as a parameter and can also return a function. You can have functions with no name as well. Clearly, this gives you the ability to code in functional programming style.

4. Support for objects

Javascript is an object oriented language. However, the way javascript handles objects and inheritance is bit different from conventional object oriented programming languages like Java. Due to this, javascript supports most of the object oriented concepts while being simple to learn and use.

These are some of the features that give javascript an ability to handle simple as well as complex tasks. Due to this, javascript has remained as the most popular programming language for a long time. It is also a good language for people who want to learn computer programming as it supports object oriented as well as function concepts and to use it, you just need a browser and a text editor.

by munaza Wed Sep 07, 2011 10:13 am

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Javascript An Introduction

Javascript An Introduction

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