Obtaining jQuery

The official jQuery website (http://jquery.com/) is always the most up-to-date resource for code and news related to the library. To get started, we need a copy of jQuery, which can be downloaded right from the home page of the site. Several versions of jQuery may be available at any given moment; the latest uncompressed version will be most appropriate for us.

Installing jQuery
No installation is required for jQuery. To use jQuery, we just need to place it on our site in a public location. Since JavaScript is an interpreted language, there is no compilation or build phase to worry about. Whenever we need a page to have jQuery available, we will simply refer to the file's location from the HTML document.

jQuery Anatomy's

A typical jQuery script uses a wide assortment of the methods that the library offers. Selectors, DOM manipulation, event handling, and so forth come into play as required by the task at hand. In order to make the best use of jQuery, we need to keep in mind the wide range of capabilities it provides.

This blog will itemize every method and function found in the jQuery library. Since there are many methods and functions to sort through, it will be useful to know what the basic categories of methods are, and how they come into play within a jQuery script. Here we will see a fully functioning script, and examine how the different aspects of jQuery are utilized in each part of the script.

Before we reveal the script that performs some tasks, we should walk through the environment in which the script resides
1.Obtaining jQuery, the tutorial to obtaining jQuerys is available here: http://tutorial-jquery.blogspot.com/2010/06/obtaining-jquery.html
2. Setting Up the HTML Document
3. Writing the jQuery Code

Why jQuery Works Well

With the recent resurgence of interest in dynamic HTML comes a proliferation of JavaScript frameworks. Some are specialized, focusing on just one or two of the above tasks. Others attempt to catalog every possible behavior and animation, and serve these all up pre-packaged. To maintain the wide range of features outlined above while remaining compact, jQuery employs several strategies:
  • Leverage knowledge of CSS. By basing the mechanism for locating page elements on CSS selectors, jQuery inherits a terse yet legible way of expressing a document's structure. Because a prerequisite for doing professional web development is knowledge of CSS syntax, jQuery becomes an entry point for designers who want to add behavior to their pages.
  • Support extensions. In order to avoid feature creep, jQuery relegates special-case uses to plug-ins. The method for creating new plug-ins is simple and well-documented, which has spurred the development of a wide variety of inventive and useful modules. Even most of the features in the basic jQuery download are internally realized through the plug-in architecture, and can be removed if desired, yielding an even smaller library.
  • Abstract away browser quirks. An unfortunate reality of web development is that each browser has its own set of deviations from published standards. A significant portion of any web application can be relegated to handling features differently on each platform. While the ever-evolving browser landscape makes a perfectly browser-neutral code base impossible for some advanced features, jQuery adds an abstraction layer that normalizes the common tasks, reducing the size of code, and tremendously simplifying it.
  • Always work with sets. When we instruct jQuery, Find all elements with the class 'collapsible' and hide them, there is no need to loop through each returned element. Instead, methods such as .hide() are designed to automatically work on sets of objects instead of individual ones. This technique, called implicit iteration, means that many looping constructs become unnecessary, shortening code considerably.
  • Allow multiple actions in one line. To avoid overuse of temporary variables or wasteful repetition, jQuery employs a programming pattern called chaining for the majority of its methods.
This means that the result of most operations on an object is the object itself, ready for the next action to be applied to it. These strategies have kept the jQuery package slim—roughly 20KB compressed—while at the same time providing techniques for keeping our custom code that uses the library compact, as well. The elegance of the library comes about partly by design, and partly due to the evolutionary process spurred by the vibrant community that has sprung up around the project. Users of jQuery gather to discuss not only the development of plug‑ins, but also enhancements to the core library. There is many of the community resources available to jQuery developers.

Despite all of the efforts required to engineer such a flexible and robust system, the end product is free for all to use. This open-source project is dually licensed under the GNU Public License (appropriate for inclusion in many other open-source projects) and the MIT License (to facilitate use of jQuery within proprietary software).

What jQuery Does

The jQuery library provides a general-purpose abstraction layer for common web scripting, and is therefore useful in almost every scripting situation. Its extensible nature means that we could never cover all possible uses and functions in a single book, as plug‑ins are constantly being developed to add new abilities. The core features, though, address the following needs:
  • Access parts of a page. Without a JavaScript library, many lines of code must be written to traverse the Document Object Model (DOM) tree, and locate specific portions of an HTML document's structure. jQuery offers a robust and efficient selector mechanism for retrieving exactly the piece of the document that is to be inspected or manipulated.
  • Modify the appearance of a page. CSS offers a powerful method of influencing the way a document is rendered; but it falls short when web browsers do not all support the same standards. jQuery can bridge this gap, providing the same standards support across all browsers. In addition, jQuery can change the classes or individual style properties applied to a portion of the document even after the page has been rendered.
  • Alter the content of a page. Not limited to mere cosmetic changes, jQuery can modify the content of a document itself with a few keystrokes. Text can be changed, images can be inserted or swapped, lists can be reordered, or the entire structure of the HTML can be rewritten and extended—all with a single easy-to-use API.
  • Respond to a user's interaction with a page. Even the most elaborate and powerful behaviors are not useful if we can't control when they take place. The jQuery library offers an elegant way to intercept a wide variety of events, such as a user clicking on a link, without the need to clutter the HTML code itself with event handlers. At the same time, its event‑handling API removes browser inconsistencies that often plague web developers.
  • Add animation to a page. To effectively implement such interactive behaviors, a designer must also provide visual feedback to the user. The jQuery library facilitates this by providing an array of effects such as fades and wipes, as well as a toolkit for crafting new ones.
  • Retrieve information from a server without refreshing a page. This code pattern has become known as Asynchronous JavaScript and XML (AJAX), and assists web developers in crafting a responsive, feature-rich site. The jQuery library removes the browser-specific complexity from this process, allowing developers to focus on the server-end functionality.
  • Simplify common JavaScript tasks. In addition to all of the document‑specific features of jQuery, the library provides enhancements to basic JavaScript constructs such as iteration and array manipulation.

Leaning jQuery: The Beginning

Today's World Wide Web is a dynamic environment, and its users set a high bar for both style and function of sites. To build interesting, interactive sites, developers are turning to JavaScript libraries such as jQuery to automate common tasks and simplify complicated ones. One reason the jQuery library is a popular choice is its ability to assist in a wide range of tasks.

Because jQuery does perform so many different functions, it can seem challenging to know where to begin. Yet, there is a coherence and symmetry to the design of the library; most of its concepts are borrowed from the structure of HTML and Cascading Style Sheets (CSS). Because many web developers have more experience with these technologies than with JavaScript, the library's design lends itself to a quick start for designers with little programming experience. In fact, in this opening chapter we'll write a functioning jQuery program in just three lines of code. On the other hand, experienced programmers will also be aided by this conceptual consistency, as we'll see in the later, more advanced chapters.

But before we illustrate the operation of the library with an example, we should discuss why we might need it in the first place.
Okey, let's begin, at first you may ask "What you have to know, before learning jQuery?"

Here's what you should learn before starting to learn jQuery:
Better yet, if you complete your reading of the standard HTM / XHTML, XML.
2. CSS
How do you use a CSS Selector? id or classes?
3. JavaScript
Mastering Java Sript important so that you can compare the use JavaSript without jQuery with jQuery itself.

What you can do using jQuery?
1. Ease of access document element.
2. Modification of web page views.
3. Changing the contents of the document.
4. Responding to user interaction.
5. Animating: about changes made to the document.
6. Retrieving information from a server without a page refresh.
7. Simplified JavaScript common tasks.

jQuery, whether it's food? (Chapter 2)

jQuery is a powerful JavaScript library that can enhance your websites regardless of your background.
Created by John Resig, jQuery is an open-source project with a dedicated core team of top-notch JavaScript developers. It provides a wide range of features, an easy-to-learn syntax, and robust cross-platform compatibility in a single compact file. What's more, over a hundred plug-ins have been developed to extend jQuery's functionality, making it an essential tool for nearly every client-side scripting occasion.
Learning jQuery provides a gentle introduction to jQuery concepts, allowing you to add interactions and animations to your pages—even if previous attempts at writing JavaScript have left you baffled. This blog guides you past the pitfalls associated with AJAX, events, effects, and advanced JavaScript language features.

jQuery? Is it Free?
Yes, jQuery is for free. jQuery is available in two types of MIT and the GPL license. You can choose which license is right for you.

I'm an Programmer for particular programming language, is jQuery right for me?
Oh, it depends on you ... :)
I can not answer that, importantly, jQuery is not more difficult than other Java Script framework.

Suitable to be applied, whether it's your ASP programmers, PHP, JSP, Rails, and others. Surely during your goal is to use jQuery to manipulate the DOM using Java Script.

Who's already using jQuery?
Among others: Google, Amazon, IBM, Microsoft, Twitter, Intel, Oracle, Digg, Dell, and others.
A complete list of sites that use jQuery can you see here: http://docs.jquery.com/Sites_Using_jQuery

Want to try? Download jQuery ...
Download jQuery on jQuery's official website. http://www.jquery.com

jQuery, whether it's food?

jQuery, whether it's food?
Before we started using jQuery is a good idea that we understand exactly what jQuery.
As mentioned in jQuery official website, (www.jquery.com), jQuery is::
Java Script Library is designed to summarize / facilitate the handling of HTML documents, handle events, Animation, and Ajax interactions. jQuery is designed to change the way you write Java Script.
Is that all?
Yes, that's all.
If you are accustomed scripting with JavaScript, you will discover the pleasure of using jQuery. You no longer need to write hundreds of lines of Java Script. jQuery make it simple.

Why jQuery? Is not there a lot of Java Script libraries other, more powerful?
Maybe you're stuck on this blog because I was looking for Java Script libraries which ones should you use and start comparing to make a choice. Whatever your choice, that is best for you.
But, believe me, jQuery is easier to learn compared to other similar Java Script libraries. This is where the excess, jQuery is more well-documented. Tutorials, plugins and the UI is also very much (try for googling..). Very suitable for beginners in programming due to jQuery AJAX is not used for functions outside the DOM is very complex.Please read an interesting article about the comparison with Mootools jQuery here: http://jqueryvsmootools.com/