Why is JavaScript so Popular in Web Development?

Over the years JavaScript has come to be the most popular language of the web, but why? How did this come to be?

Perhaps the most influential factor tying JavaScript to web development is the fact that it was developed precisely for that purpose; well kind of. Netscape originally created JavaScript for use in it's browser so that web developers could manipulate various features of websites such as creating hover events on buttons and checking form data before it was sent to the server. During these early years JavaScript was regarded as a toy language and it's developers as amateurs at best.

However, the true power of JavaScript could not be realized at this time. Despite the fact that JavaScript had become the first cross browser client side language by being included in Netscape's largest competitor's browser Internet Explorer cross browser inconsistencies plagued developers. This was not because each browser parsed the language differently, but because they all had their own different level of support and interpretations for the key technologies of the web namely HTML, CSS, and the DOM.

To counteract these inconsistencies other technologies were developed such as Java Applets and Adobe Flash which required plug-ins to work. These plug-ins insured consistent behavior across browsers, but they also frequently had large file sizes, high resource requirements, and security issues. They also had no ability to actually manipulate the building blocks of websites, their HTML and CSS, like JavaScript. They just circumvented these elements by encapsulating behavior withing their own little environments. So plug-ins didn't really solve the problem they just ignored it and while this created functionality it also crippled such important features such as accessibility and indexing by search engines.

Fortunately, at the turn of the century browsers started to adhere more closely to standards defined for HTML, CSS, and the DOM. Open source libraries were also starting to be developed and distributed whose sole purpose was to hide the complexity of browser inconsistencies behind an easy to use and extensible programming interface. For the first time in web history there was enough consistency for web developers across browsers to develop large complex programs with relative ease. Not only was JavaScript available on all browsers, but also all operating systems with a single code base!

Programmers now looked at JavaScirpt as a true programming language worthy of serious consideration as the code of choice for future applications. Some of it's most admired features were it's small learning curve and flexible variables, classes, and objects. It was also an interpreted language which allowed for very quick prototyping though rapid cycles of coding, testing, and debugging. Combine this with the fact that all of the classes within the language could be extended and new classes created and the power of reusable libraries became apparent.

With browser inconsistencies disappearing and JavaScript getting serious consideration from professional programmers the stage was set for JavaScript to become not only the dominant language of the web, but also perhaps one of the most dominant languages of application development. With the advent of Ajax, a technology that allowed a website to communicate with a server without reloading the page, much improved network speeds, and greater processing power across devices JavaScript could finally do the work formally reserved for compiled desktop applications written in languages such as C. JavaScript's dominance has been further accelerated by the recent advents of cloud based computing and storage which allow for completely web based applications. Finally, Google's release of Node.js may have even made JavaScript a true competitor for server side languages as well which would mean JavaScript would run almost everything on the web!

Truly JavaScript is no longer a 'toy' language and it's future as the language of the web is exciting!