This article discusses the good and the bad points of using JavaScript in your website designs. It points out the areas where JavaScript excels as a web based programming language and also describes situations where its use can actually detract from the performance of a website.

First of all, JavaScript is a browser based programming language that actually runs client side. This means that any code that you write in JavaScript is delivered along with your web pages and the scripts that you write actually run from within the users’ browser rather than directly on the server that is serving the web page. There are situations where JavaScript is an excellent solution for implementing neat features in a web design but there are also situations where using JavaScript can hurt your websites performance. It is my aim in this article to describe the best ways to use JavaScript and how to circumnavigate the downsides of using this versatile and powerful scripting language.

JavaScript for Web Design – The Advantages

JavaScript is an excellent solution to implement when validating input forms on the client side. This means that if a user forgets to enter his name in a form for instance a JavaScript validation function can popup a message to let him know about the omission. This is a far better solution that having a server side validation routine handle the error because the server does not have to do any additional processing. An asp or php routine could be written to achieve the same task but the JavaScript would not allow the form to be submitted unless it was completed properly in the first place, a much more robust solution!

Another area where JavaScript excels is in the creation of dynamic effects such as rollover images and scripted slideshows, where its use has become commonplace. Because JavaScript runs inside the clients browser it can be used to change the appearance of the users screen after the page has been sent by the server. This allows it to create some very impressive dynamic image effects.

JavaScript for Web Design – The Disadvantages

One of the major draw backs to using JavaScript is that it tends to severely bloat web pages. JavaScript code can quickly add up to hundreds of lines of code if you are using it to do anything even remotely interesting. That said the problem of large chunks of JavaScript code is easily solved by storing the JavaScript code off into separate JavaScript source files that have a .js extension. This cleans up your web page code because the JavaScript code is stored separately to the HTML page itself, leaving a much cleaner and more readable web page.

Because of JavaScript’s tendency to bloat web pages it can be very detrimental to the search engine friendliness of your web site. This is because when a search engine arrives at your site looking for quality content and keywords to determine what your page is al about, the last thing it wants to see is hundreds of lines of JavaScript code. Again, this problem is easily solves by neatly storing JavaScript code away in script files with a .js extension and linking to the script file in your HTML documents.

Conclusion:

JavaScript is a feature rich and useful browser based script that if used properly can achieve some great effects and improve the experience for the end user. There are drawbacks to its use in that it tends to bloat web pages. The key thing to remember is to get the best of both worlds by using JavaScript code in external script files. That way the code is separated from your content so you get all the benefit of JavaScript functionality but without the adverse effects of the associated code bloating.