jQuery
jQuery is a multi-browser
JavaScript library designed to simplify the client-side scripting of HTML. It
was released in January 2006 at BarCamp NYC by John Resig. It is currently
developed by a team of developers led by Dave Methvin. Used by over 65% of the
10,000 most visited websites, jQuery is the most popular JavaScript library in
use today.
jQuery is free, open source
software, licensed under the MIT License. jQuery's syntax is designed to make
it easier to navigate a document, select DOM elements, create animations,
handle events, and develop Ajax applications. jQuery also provides capabilities
for developers to create plug-ins on top of the JavaScript library. This
enables developers to create abstractions for low-level interaction and
animation, advanced effects and high-level, theme-able widgets. The modular
approach to the jQuery library allows the creation of powerful dynamic web pages
and web applications.
Microsoft and Nokia have
announced plans to bundle jQuery on their platforms. Microsoft is adopting it
initially within Visual Studio for use within Microsoft's ASP.NET AJAX
framework and ASP.NET MVC Framework while Nokia has integrated it into their
Web Run-Time widget development platform. jQuery has also been used in
MediaWikisince version 1.16.
Features
jQuery includes the following features:
Ø
DOM element selections using the multi-browser
open source selector engine Sizzle, a spin-off out of the jQuery project
Ø
DOM traversal and modification (including support
for CSS 1-3)
Ø
DOM manipulation based on CSS selectors that uses
node elements name and node elements attributes (id and class) as criteria to
build selectors
Ø
Events
Ø
Effects and animations
Ø
AJAX
Ø
Extensibility through plug-ins
Ø
Utilities - such as user agent information,
feature detection
Ø
Compatibility methods that are natively available
in modern browsers but need fall backs for older ones - For example the
inArray() and each()functions.
Ø
Multi-browser (not to be confused with
cross-browser) support.
Ø
easy to implement.
jQuery plug-ins
Because of jQuery's architecture,
other developers can use its constructs to create plug-in code to extend its
functionality. Currently there are thousands of jQuery plug-ins available on
the web that cover a wide range of functionality such as Ajax helpers, web
services, data grids, dynamic lists, XML and XSLT tools, drag and drop, events,
cookie handling, modal windows, even a jQuery-based Commodore 64 emulator.
An important source of jQuery
plug-ins is the Plugins sub-domain of the jQuery Project website. However, in
an effort to rid the site of spam, the plugins in this sub domain were
accidentally deleted in December 2011. The new site will include a
GitHub-hosted repository, which will require developers to resubmit their
plugins and to conform to new submission requirements. There are alternative
plug-in search engines like jQuery. in that take more specialist approaches,
such as listing only plug-ins that meet certain criteria (e.g. those that have
a public code repository). The tutorials page on the jQuery site has a list of
links to jQuery plug-in tutorials under the "Plugin development"
section.
Release history
Version
number
|
Release
date
|
Additional
notes
|
1.0
|
August 26, 2006
|
First stable release
|
1.1
|
January 14, 2007
|
|
1.2
|
September 10, 2007
|
|
1.3
|
January 14, 2009
|
Sizzle Selector Engine
introduced into core
|
1.4
|
January 14, 2010
|
|
1.5
|
January 31, 2011
|
Deferred callback
management, Ajax module rewrite
|
1.6
|
May 3, 2011
|
Significant performance
improvements to the attr() and val() functions
|
1.7
|
November 3, 2011
|
New Event APIs: .on() and
.off(), while the old APIs are still supported.
|
1.8.0
|
August 9, 2012
|
Sizzle Selector Engine
rewritten, improved animations and $(html, props) flexibility.
|
1.9.0
|
January 15, 2013
|
Removal of deprecated
interfaces and code cleanup
|
1.9.1
|
February 04, 2013
|
|
2.0.0
|
Dropped IE6-8 support for
performance improvements and reduction in file size
|