Making connection to database in Wordpress for Ajax files

include_once('../../../../wp-config.php');
include_once('../../../../wp-load.php');
include_once('../../../../wp-includes/wp-db.php');

Web 3.0 Concepts Explained in Plain English (Presentations)

Web 1.0 – That Geocities & Hotmail era was all about read-only content and static HTML websites. People preferred navigating the web through link directories of Yahoo! and dmoz.

Web 2.0 – This is about user-generated content and the read-write web. People are consuming as well as contributing information through blogs or sites like Flickr, YouTube, Digg, etc. The line dividing a consumer and content publisher is increasingly getting blurred in the Web 2.0 era.

Web 3.0 – This will be about semantic web (or the meaning of data), personalization (e.g. iGoogle), intelligent search and behavioral advertising among other things.

If that sounds confusing, check out some of these excellent presentations that help you understand Web 3.0 in simple English. Each takes a different approach to explain Web 3.0 and the last presentation uses an example of a "postage stamp" to explain the "semantic web".

ULR: http://www.labnol.org/internet/web-3-concepts-explained/8908/

How to use Custom fields of Wordpress

http://www.wpbeginner.com/wp-tutorials/wordpress-custom-fields-101-tips-tricks-and-hacks/

Free Tutorials

http://www.lynda.com/home/otl.aspx?btn=dcp

Wordpress Development

Great website for wordpress developers where you can find lot of plugins... below is the link of the website
http://www.gopiplus.com/work/

Web Developments tool tips, form validation ect

Visit the below link for web development expertise in php..
http://www.dhtmlgoodies.com 

Top 10 CSS Table Designs

Here is top 10 css table designs, hope its will help you a lot.. click on the below link you will redirect to the orginal website from where you will download it and you will find the tutorial as well.
http://coding.smashingmagazine.com/2008/08/13/top-10-css-table-designs/

ENJOY! :)