What’s the big deal with having your content in a separate file anyway? Beyond SEO and the single responsibility principle there is what I consider to be the single most important reason: Accessibility.
When I write about accessibility I really am talking about 508c compliance. If the person viewing your web site is hard of sight or cannot see at all then your site is worthless to them. I won’t go into the legal reason of why your sites should be accessible (search “Target accessibility web site” to know more about that). Your site should function without the flashy bells and whistles that CSS, JavaScript, and Silverlight provide. The page should make sense to navigate in its pure text form. You should have main site navigation, but perhaps that should be near the bottom of the page. The most important thing about the page is the content, not the navigation. Maybe have a named link at the top of the page to quickly scroll to the navigation section, but make sure that the site content is first on the page.
The site navigation should be simple and you should have a site map. All of these suggestions are SEO best practices, but really you are doing a favor for anyone that is coming to your site that relies on a screen reader to navigate the web.
I’m not going to go through all the best practices of accessibility here, I’m sure over time I’ll compile a full list of suggestions. Just know that you need to keep this in mind as you are building your site. If your HTML is clean and free of design elements or extra JavaScript cluttering up the page your are well on your way to building an accessible site.
Since writing the content HTML is the first step of building a site. Launch it. Use the site without CSS or JavaScript. Can you get to all the content. If you turn off images, is there enough information on the screen to understand what the image was?
Once you’ve reached this step you can do two more things. You can build a simple CSS for people that want to print your site. In this print version of your CSS turn off the navigation and anything that is not content.
Next add a little bit of flair with CSS to your site and make things look better than 12pt black Times New Roman on white background. Throw in a little color and some font sizes here and there. Use this as the WAP version of your site.
Constantly building from the rock solid framework of content only HTML and adding CSS and JavaScript using external files will help you create a site that can be used on all of the lowest common denominator systems out there.
Once you’ve finished with this, you can finally go to the holy land… Silverlight. This is when you can turn on all of the bells and whistles. You will need to invest some time in writing an HTML to XAML converter, but it will be worth it. When you launch your site and everyone on the Internet can enjoy your site you will have a site worth being enjoyed.
