Internet Explorer, created by microsoft has been the most popular web browser for many years. But the gap is shrinking with the release of Mozilla Firefox, by an open source community.

At the last count it is said that there are 64 million firefox users on the internet. Growing in massive numbers by the day.

So, the issue with browser compatibility is at its highest importance. The way browsers are constructed, they can show a webpage slightly differently.

For instance, the IFRAME tag shows perfectly in Internet Explorer but does not show in Firefox. This is only one of many instances of none browser compatibility.

Therefore, webmasters should be making sure their web page is viewable in both internet explorer and firefox equally. If it doesnt, then they risk loosing a large percentage of web users. There is nothing worse than surfing a web site and not being able to see it properly in a particular browser.

The solution for webmasters is to make all their pages XHTML transitional. Web sites that validate to this, have a higher chance of being viewed correctly in all major browsers.

XHTML is the next generation web language, and is said to replace HTML eventually. XHTML was released in January 2000.

XHTML is not a difficult language to learn, it is basically identical to HTML but the main difference is that tags in XHTML always have an end tag.

For example, a IMG SRC tag in HTML has no end tag. In XHTML the IMG SRC tag has the end tag of />

More information on learning XHTML can be found at w3schools.com - xhtml - intro

Once you have constructed your XHTML web page then you can validate it at W3schools.comxhtml - xhtml validate

Further, to ensure near complete browser compatibility you can validate any stylesheet here : Jigsaw.w3.org - CSS-Validator.