How it’s Done! (Part I): Building High Performance Web Sites

Yahoo’s exceptional performance team identifies 14 rules for making web pages faster, as itemized below:

1. Make Fewer HTTP Requests
2. Use a Content Delivery Network (CDN)
3. Add an Expires Header
4. Gzip Components
5. Put CSS at the Top
6. Move Scripts to the Bottom
7. Avoid CSS Expressions
8. Make JavaScript and CSS External
9. Reduce DNS Lookups
10. Minify JavaScript
11. Avoid Redirects
12. Remove Duplicate Scripts
13. Configure ETags
14. Make Ajax Cacheable

You can find a more in-depth discussion about these best practices in the Network Blog or from Steve Sounder’s (Cheif Performance Yahoo!) book on “High Performance Web Sites – Essential Knowledge for Front-End Engineers“.

More so, if these rules mean anything to you, you might want to check out “YSlow“. YSlow analyzes web pages and tells you why they’re slow based on these rules for high performance web sites. Note, you must install Firebug first.

If you don’t already have Firebug, download it today. It is a Firefox add-on very useful for debugging, editting, and monitoring client-side code (CSS, HTML, and JavaScript) live in any web page.