Ever wondered why your site tends to load slowly, even though you have broadband connection? Well, it might be because your site is not adhering to the 13 Rules for High Performance Web Sites. Thankfully there is now a tool out that lets you check, what is going wrong and what you can do to speed up your site.
Put together by Steve Souders and The Exceptional Performance team at Yahoo! and presented to the public by Nate Koechley during @media, these rules are:
- Make Fewer HTTP Requests
- Use a Content Delivery Network
- Add an Expires Header
- Gzip Components
- Put CSS at the Top
- Move Scripts to the Bottom
- Avoid CSS Expressions
- Make JavaScript and CSS External
- Reduce DNS Lookups
- Minify JavaScript
- Avoid Redirects
- Remove Duplicate Scripts
- Configure ETags
You will find detailed explanations about these rules if you follow the links to the Yahoo! Developer Network. From a developers point of view, you finally have some benchmarks that you can test your site against and, what is more important, the rules also tell you how to resolve eventual issues. Although, some of these rules might not apply if you are only hosting a small to medium-sized website. Using a CDN, if you only have a few media files on your site, does not really make much sense. So still apply some common sense before executing any changes to your site based on these rules.
Furthermore, a very useful extension to Firefox has been released just recently. YSlow requires Firebug (and Firefox 2.x) to be already installed and lets you check any website against the rules mentioned above. So if you are a developer who does care about how your site performs, I do strongly recommend adding this to your Firefox extension repository.
If you want more, you can have it. Steve, Chief of Performance at Yahoo!, also published a book on that topic, which you also might want to add to your Web Development bookshelf.