The document discusses why jQuery is a useful library. It notes that jQuery code is very easy to use and accomplishes a lot with only a few lines. It also provides powerful DOM manipulation, AJAX capabilities, and basic animations without much overhead. jQuery was released in 2006 and grew rapidly in popularity due to playing well with other libraries, built-in support for common tasks like AJAX, and producing succinct, readable code in a small file size.

1.  Why I should use jQuery?
 Simple. In just one glance at the source code of a
page using jQuery you’ll see how easy it is to use,
how much it accomplishes in so few lines of code,
and how graceful it is.
 My mind was opened one day when I stumbled
across some code written with jQuery. I was flipping
through the RSS feeds and reading my daily dose of
web design blogs when I came across an example of
JavaScript loveliness that used jQuery. Truth be told,
the code on that site had some browser related
bugs… but the concept was something I hadn’t seen
before.

2.  What about the code?
 The code looked almost simple. Like
nothing I had seen before. It made
sense.
 I started reading through the
documentation and was amazed to see
how much could be done with so little
extra code.

3.  When you can use jQuery?
 You should use jQuery when you need:
 A small library that gives you powerful control over the
Document Object Model
 With very little effort or work on your part
 Or
 Quick access to AJAX
 Without a lot of bloat (overhead - wasted code)
 And some basic animation effects to spice things up
 But…
 If you need super fancy effects for animation, drag and
drop, and super smooth animation then you’ll probably
want to use Prototype and one of the many great library
created to enhance the effects.

5.  Released January 14, 2006 by John Regis
 Rapid popularity growth
 Play well with other libraries
 Built in Support with AJAX, Events and
Animations
 Succinct Code, Small File Size
 Java Script for Designers

6.  DOM element selections
 DOM traversal and modification,
(including support for CSS 1-3 and basic
XPath)
 Events
 CSS manipulation
 Effects and animations
 Extensibility

7.  Light weight compared to other Libraries
 Have a wide range of plug-ins
 Lot simpler than other Libraries
 Shorter codes are used