Introducing jQuery

To fully understand jQuery and its applications in modern web programming, it's important to take a moment and look back at where jQuery came from, what needs it was built to fill, and what programming in Java Script was like before jQuery came around.

In this you'll learn about JavaScript libraries and the needs they seek to fulfill, as well as why jQuery is the library of choice for the majority of web developers. You'll also learn the basics of jQuery, including how to make the library available for use in your applications and how the core of jQuery—its powerful selector engine—works.

JavaScript has a reputation for being rather unwieldy in web applications. A lack of consistent browser support, difficult debugging, and an intimidating syntax can make learning JavaScript feel impossible. To be fair, all the things that make JavaScript seem difficult are part of what make it so powerful, but that doesn't make it any more inviting to a novice web developer looking to add JavaScript to his arsenal.

Understanding JavaScript Libraries

The steep learning curve associated with JavaScript has been a sore spot for developers for years, and as frustrations grew, several ambitious developers started building JavaScript libraries, also referred to as JavaScript frame works. These libraries aimed to simplify the use of JavaScript to make it more accessible to both new and existing developers by creating easy-to-use control functions that remove some of the heavy lifting from everyday JavaScript tasks. Libraries are especially useful in the realm of Asynchronous JavaScript and XML (AJAX) due to the complexity of performing the same tasks using straight JavaScript. JavaScript libraries aim to provide a simpler syntax for common tasks, which translates to a faster workflow for developers and a less intimidating learning curve for beginners. They also eliminate some of the headache involved in coding cross-browser. JavaScript by doing all the compatibility checks for you within their built-in methods, which is a huge time-saver when coding.

Understanding the Benefits of jQuery

Every JavaScript framework has its own benefits; jQuery is no exception, providing the following benefits:

• Small ile size (approximately 23KB as of version 1.4)
• Extremely simple syntax
• Chainable methods
• Easy plug-in architecture for extending the framework
• A huge online community
• Great documentation at
• Optional extensions of jQuery for added functionality, such as jQueryUI

Understanding the History of jQuery

The brain child of developer John Resig jQuery was first announced at BarCamp NYC in early 2006 (for more on BarCamp. Resig noted on his web site, that he created jQuery because he wasunhappy with the currently available libraries and felt that they could be vastly improved by reducing “syntactic fluff” and adding specific controls for common actions. jQuery was a big hit in the development community and quickly gained momentum. Other developers came on to help refine the library, ultimately resulting in the first stable release of jQuery, version 1.0, on August 26, 2006. Since then, jQuery has progressed to version 1.4.2 (at the time of this writing) and has seen a huge influx of plug-ins from the ndevelopment community. A plug-in is an extension of jQuery that isn’t part of the core library.