Anyone who’s ever designed a website for themselves or for anyone else should have considered the cross-browser issue. A lot of times, the same content will appear differently from one browser to the next, which is a huge pain. You’ve spent a lot of time and effort to make your page look great, but there’s always going to be cross-browser concerns when it comes to the web.

The same problems arise when delivering a CMS solution to your clients. You have to be concerned about this on both fronts, the backend and the frontend. You need to be aware that your CMS (if it happens to be browser-based) might not always be loaded on the same browser or operating system for that matter that your clients are going to use. Depending on your contract, you might be permitted to enforce one standard on them, but as a developer you can’t count on that. On the frontend, you have to be sure the content you or your clients are producing won’t have the same problems showing in both browsers. This can be a tough one, because there’s never any way to know what a user is going to do with your software once it leaves your graces!

The good news is that most browsers are subscribing to XHTML and XML (of which HTML is a subset of tags) compliance. This is to say that for most formatting options, you are able to force a browser to display content according to a set of rules which exist for the content, independent of the browser. Implementing this is simple, but enforcing XHTML or XML compliance might uncover some things about your own coding and authoring style which you didn’t know you were doing incorrectly.

To force XML or XHTML compliance, you only need to add a single tag to your pages: The DOCTYPE tag. This tag looks like this:

It goes before the opening tag on your pages. In the example above, we’re specifying that the current page subscribes to the XHTML 1.0 protocol. This forces the browser to display the HTML as XHTML. *You might see somethings wrong which weren’t wrong before.*

I recommend all your pages include this tag. It will eliminate or really reduce the formatting gaps you’ve been seeing between Firefox and Internet Explorer, and Opera, and Safari…