jQuery Overview

Hi Welcome to my blog!

This is my first blog on jQuery. 

 In this blog we will learn the following topics:

• What is jQuery
• Benefits of using jQuery
• jQuery browser compatibility
• Downloading and Installing jQuery, and
• Creating a sample your first jQuery enabled page
• jQuery features

1. What is jQuery

• It is a free, open Javascript library
• It simplifies the task of creating highly responsive web pages
• It works across all modern browsers (list of browsers are listed in this blog later)
• It abstracts away browser-specific features, allowing you to concentrate on design
• It focuses on simplifying common scripting tasks like
  

             - Getting and manipulating page contents

             - Working with the modern browser event model

             - Adding sophisticated effects

• Most modern web development scenarios involve common patterns like

            - page loads where you perform a bunch of page setup, and

            - event where you retrieve content from the page, manipulate 
              or animate the content, and put the  content back in the page

• jQuery make these scenarios easy

2. Benefits of using jQuery

• Leverages your existing knowledge of CSS (Cascading Style Sheet)
• Works with sets of elements
• Performs multiple operations on a set of elements with one line of code (known as statement chaining)
• Hides various browser quirks (so you can concentrate on the end result)
• Is extensible (so you can use third-party-plug-ins to perform specialized tasks, or write your own)

3. jQuery browser compatibility

• jQuery currently compatible with all modern browsers in use today

Browser                         With with                          Known issues with

Internet Explorer             6.0 and greater                 1.0 through 5.x

Safari                            3 and greater                    1.0 through 2.1

Chrome                         1 and greater                     N/A

Firefox                           2 and greater                    1.0.x

Opera                            9 and greater                    1.0 through 8.x

4. Downloading and Installing jQuery

• You can download the jQuery from http://jquery.com/  
• jQuery comes in two versions: production (which is compressed and minified) and development
• Typically, you download both versions and then use each one for its intended purpose

5. Creating a first simple jQuery enabled page

• typically, code that you want to execute when the page is loaded is written like this:

       
         function RunOnLoad( ) {

              alert("Page loaded!");

    }

         window.onload = RunOnLoad;

•  The on-load event only fires after all of the page content has downloaded, including images
• It's also harder to add multiple load functions
• jQuery provides a way to run code when the DOM of the page is ready. This is called the document.ready event
• The document.ready event is written like this:

           $("document").ready( function ( ) {

                  alert("Page just loaded!");

     });

• This code will now executed when the DOM has loaded, instead of waiting for all of the page content finish downloading
• also, you can call document.ready funtion multiple times, and jQuery will chain together each one to be called in succession

6. jQuery features:

The features break down across eight major categories:

1. Core Functionality: Implements core jQuery functions as well as commonly used utilities

2. Selection and Traversal: Provides functions for finding content in documents and navigating among the contents of the document

3. Manipulation and CSS: Provides functions for editing and changing documents content and working with CSS data such as positioning info

4. Events: Simplifies working with the modern DOM events and provides common event helper functions

5. Effects: Provides functions for creating basic animations and effects, such as hiding and showing elements and moving objects around

6. Ajax: Provides utilities for working with Ajax, such as loading content from pages and dealing with JSON data

7. User Interface: Provides an official plug-in with commonly used interface widgets, like slider controls, progress bars, accordions, etc

8. Extensibility: Enables the construction of jQuery plug-ins that enhance the functionality of the base library

We will explore each of these functionality in details in my coming blogs.
So keep watching my blogs.