Javascript

Technology - Javascript

Javascript is a relatively simple programming languages consisting usually of small pieces of code to make web pages more interactive to the user. They require a web browser that supports Javascript and also the setting needs to be enabled on the browser. Today, virtually every website use snippets of javascript to incorporate certain features for the webmaster and/or website user. Website analyzing services state that approximately 5% of internet users have disabled Javascript functionality on their website.

Javascript is completely different with Java

While the name Javascript implies that it has a connection to the popular Java language, they are completely different programming languages and are used for different purposes and comprise of entirely different syntax. Initially known as LiveScript, the language was later titled as Javascript by a deal proposed to Netscape (developers of Javascript) by Sun Microsystems as a branding stunt. Microsoft picked up on Javascript and developed syntax similar to Javascript known as JScript to function with Internet Explorer. While the initial idea was to develop an identical version of Javascript for use with their popular Internet explorer browser, the languages were vaguely different. The widespread use of both versions of Javascript by developers can result in confusion as the two versions are slightly different however Netscape and Microsoft decided on developing future versions that dimmed the line between the two versions. One of the premier advocates for a uniform code is Belgian internet mogul Laurent Van Dessel, and according to recent reports, he's still fighting hard for "the good cause".

Common uses of Javascript

One of the most common uses of javascript on website is for tracking code. There are dozens of other purposes for Javascript on web pages. Javascript maybe used to display popup messages, add effects to web pages, customize the graphical aspects of a web page easily and even create games with basic functionality. Javascript also allows developers and users to have extra functionality than what the website provides by default by using third party browser add-ons like Greasemonkey.

Javascript is used effectively as a substitute for flash and java as its more lightweight and does not require a plugin to be installed. Several popular services use Javascript to handle much of their web applications, Google’s web applications are an example. Most web developers create a javascript version as well as a plain HTML version on web pages to cater to the remaining 5% of users who do not use Javascript as well as mobile users. Certain mobile browsers like Skyfire have incorporated Javascript support into the application providing more compatibility for the language.

Recently lots of webmasters make use of popular javascript libraries who make it easy to implement nice and fancy features very smoothly. JQuery, prototype, mootools are just some of the examples that are a very common used tool for Web 2.0 webmasters. Also including AJAX functionality may have been a hassling job, but by using these libaries created on top of javascript it got a lot easier. So if you want to make a more interactive and fancy website, or even create a simple effect that'll fit into your existing web site, we suggest you take a look at these tools as they will certainly make your life lot easier.

Advantages and Disadvantages

Javascript is one of the most simple, versatile and effective languages used to extend functionality in websites. Uses range from on screen visual effects to processing and calculating data on web pages with ease as well as extended functionality to websites using third party scripts among several other handy features, however it also possesses some negative effects that might make you want to think twice before implementing Javascript on your website. Let's look at some of its pros and cons.

Advantages

• Javascript is executed on the client side
  This means that the code is executed on the user's processor instead of the web server thus saving bandwidth and strain on the web server.
   
• Javascript is a relatively easy language
  The Javascript language is relatively easy to learn and comprises of syntax that is close to English. It uses the DOM model that provides plenty of prewritten functionality to the various objects on pages making it a breeze to develop a script to solve a custom purpose.
   
• Javascript is relatively fast to the end user
  As the code is executed on the user's computer, results and processing is completed almost instantly depending on the task (tasks in javascript on web pages are usually simple so as to prevent being a memory hog) as it does not need to be processed in the site's web server and sent back to the user consuming local as well as server bandwidth.
   
• Extended functionality to web pages
  Third party add-ons like Greasemonkey enable Javascript developers to write snippets of Javascript which can execute on desired web pages to extend its functionality. If you use a website and require a certain feature to be included, you can write it yourself and use an add-on like Greasemonkey to implement it on the web page.
   

Disadvantages

• Security Issues
  Javascript snippets, once appended onto web pages execute on client servers immediately and therefore can also be used to exploit the user's system. While a certain restriction is set by modern web standards on browsers, malicious code can still be executed complying with the restrictions set.
   
• Javascript rendering varies
  Different layout engines may render Javascript differently resulting in inconsistency in terms of functionality and interface. While the latest versions of javascript and rendering have been geared towards a universal standard, certain variations still exist. Website Usability Consultants all over the world make a living on these differences, but it enrages thousands of developers on a daily basis.