Today, JQuery is being used by all the popular web giants such as Google, Microsoft, Dell, IBM, NBC, NTT Data etc. For a list of companies using JQuery you can explore http://docs.jquery.com/Sites_Using_jQuery
I remember when I was learning JavaScript; it was painful to make your JavaScript code compatible with all the browsers (Internet Explorer, Firefox, and Chrome etc.) as all the browsers parent companies (Microsoft, Google, Netscape etc.) were using different set of object model. A well written JavaScript may or may not run on each browser and the programmer were trying to first read what kind of browser is running and subsequently writing piece of JavaScript code.
JQuery solved this problem by wrapping JavaScript code into a set of rich library. Today you can use JQuery and it is compatible with all browsers. It is referred as a cross-browser JavaScript library. JQuery is free and open source. With JQuery we can easily navigate an HTML document, read DOM (document object model), handle events, do animations and create cool Ajax applications.
JQuery has moved to Mobile development as well. So you can use JQuery Mobile if you are interested to develop applications for smart phones. The cool thing about the JQuery Mobile is that it runs on all popular mobile handsets and platform.
So back to our JQuery for web development; to start with JQuery you first need to know that JQuery library comes in two flavors.
1. Hosted JQuery library.
2. Downloaded JQuery library
Hosted JQuery library: With Hosted JQuery library you do not need to download JQuery library to your system. The JQuery library is hosted with the parent companies. Google and Microsoft have provided their JQuery library to web developer community. Google hosted JQuery library is available at https://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.min.js. The JavaScript scripting file has file extension ".js". The latest version of JQuery library available with Google is 1.7.2. Microsoft hosted JQuery library is available at http://ajax.aspnetcdn.com/ajax/jQuery/jquery-1.7.2.min.js . The advantage with hosted JQuery library is you are not downloading or maintaining JQuery library. The disadvantage is to run your web pages which are using JQuery you need to be connected with internet.
Downloaded JQuery library: With Downloaded JQuery library you need to download the JQuery library to your system. The library is available for download at http://docs.jquery.com/Downloading_jQuery#Current_Release. This is provided by JQuery foundatation which is a non-profit associate and supports the development of JQuery.
The choice is ours how we want to move ahead with the JQuery uses and development. In either case we need to tell to our web page, web site that we are using JQuery and to do this all you have to do is to include following in the header section of your web page.
<head> <script type="text/javascript" src="<<JQuery Library Path>>"> </script> </head>
So if are you using Google JQuery library the header section will include following:
<head> <script type="text/javascript" language="Javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.min.js"> //JQuery Code goes here </script> </head>
If you are using Microsoft JQuery library the header section will include following:
<head> <script type="text/javascript" src="http://ajax.microsoft.com/ajax/jquery/jquery-1.7.2.min.js"> </script> </head>
We will do some example in our next topic. Till than you can download or be ready to learn JQuery.
Thanks for reading till this point
