You will find two buttons at the bottom of almost every page on RCL Concepts. They say "W3C XHTML 1.0" and "W3C CSS". These buttons link to a page which will tell you that the page is valid XHTML or CSS. I hope I haven't scared you away yet...
XHTML stands for eXtendable Hyper Text Markup Language. To put it in a very basic form this is the language used by web developers to write your website. CSS stands for Cascading Style Sheet, this is what a developer will use in order to make your website look nice. So why is this important? Well just like when you read a sentence you expect to see proper grammar. To a degree you are able to read what someone who has poor grammar is saying however, when this happens you sometimes do not get the message that the speaker (or writer) wanted you to get. The same principle applies to writing web pages. Your web browser (what you use to surf the internet) takes the language that I give it and interprets it in a way that is visually appealing to the human eye. Having valid XHTML and CSS means that I have used the proper grammar (as it were) for the web browser to read and interpret.
This is where standards come in to play. A group called the Word Wide Web Consortium (or W3C) create what would be the equivalent to a dictionary. They tell you how you should write your code for your pages. This means that everyone is writing code exactly the same (if they want valid XHTML). If you write your page using valid code then the browser should be able to decode what you said and display the page correctly. The problem with being a developer is that you have to make sure what you write works with everyone. Everyones computer is different, and it is the job of the developer to make sure that each your site's visitors (and potential clients or customers) all see the same thing. In theory if you write valid code this shouldn't be a problem. Unfortunately this is not the case. Certain web browsers are not (what we in the industry like to call) standards compliant this means that they do not comply with the standards set forth by the W3C. There are currently 4 major web browsers (Internet Explorer, Mozilla Firefox, Safari, and Opera) each of them have their own way of interpreting code. As of this post only 2 of the 4 browser are what I consider standards compliant, Safari and Opera. They both follow the XHTML and CSS spec down to the letter. As a Mac user Safari is the default browser on OS X, and I have grown to love it. When I begin the coding process I use Safari for my first round of testing. This is because I know that if I have written the code correctly Safari will display it accurately.
When I finish writing the page I then have to make sure it looks accurate in other browsers. I usually have no troubles at all with Firefox because while it isn't 100% standards compliant it does a very good job and usually works fine. On the other hand we have Internet Explorer which, to be blunt, is the worst thing that ever happened to the internet.
[Time for a history lesson
Internet Explorer was a good browser back in the days of version 3.0. However about the time Version 6.0 came out Microsoft had no competition in the browser market so they quit work on it. I believe someone at Microsoft said, "this is all that anyone could want out of a browser". This however was not the case. From a security aspect Internet Explorer 6 had more holes than Swiss Cheese. As a developer the language of the web evolved and developed more since the release of IE6. Things changed giving developers more control over what their pages were going to look like to the end user. The problem here though is that IE6 still hasn't been touched by Microsoft in years. This is when Mozilla came around and introduced their new web browser, Firefox. As people began to move over to Firefox Microsoft noticed and had to pick up the slack. They rushed out a release of IE7 which fixes some of the MAJOR bugs in IE6, along with improved security, but it still fails miserably on a standards compliance test. Microsoft said that it is dedicated to making IE8 a truly standards compliant browser. I can only hope they hold true to that commitment.]
It is a shame for us developers that the majority of people on the internet today are using Internet Explorer as their web browser, because it really limits what we have to work with if we want to provide the same experience for all users. As a developer that takes pride in my work, I will try my best to provide the same browsing experience for ALL users. It pains me to see so much waisted potential in the XHTML spec simply because the most popular browser isn't up to date enough to support it. I look forward to the day when I can write a page once and know it will look perfect in every browser using all the latest web technologies.
If you are on IE I ask that you try out one of the other 3 browsers that I have mentioned above, I guarantee you wont regret it. If you do not wish to download one of the better browser, I ask that you make sure you are running the latest version of Internet Explorer.