The first time I saw Steve Souders was at HTML5 Conference 2013 in San Francisco. Just in case you haven't heard about him, here is a heads up: He is the Head Performance Engineer at Google, previously Chief Performance at Yahoo!, Creator of YSlow. More about him, please refer to:
He gave an astonishing speech of "How fast are we going now?" as an opening speaker and I was stunned by his knowledge and contribution to the web performance world. I bought his book
right after the conference and spend 2 days to finish reading it. I am so convinced by the 14 rules which are listed in his book. All those rules are backed by some concrete data and examples. Most of those rules are just like a best practice in my daily work but I never asked why we should follow those. Quite a few rules are some knowledge I haven't touched yet, like "Avoid Redirects". In this blog, I would like to share those rules with all the web performance savvy:
1) Make fewer HTTP Requests
Make fewer HTTP requests.
2) Use a Content Delivery Network
Use a content delivery network.
3) Add an Expires Header
Add a far future Expires header to your components.
4) Gzip Components
Gzip your scripts and stylesheets.
5) Put Style sheets at the Top
Put your stylesheets in the document HEAD using the LINK tag.
6) Put Scripts at the Bottom
Move scripts to the bottom of the page.
7) Avoid CSS Expressions
Avoid CSS expressions.
9) Reduce DNS Lookups
Reduce DNS lookups by using Keep-Alive and fewer domains.
11) Avoid Redirects
Find ways to avoid redirects.
12) Remove Duplicate Scripts
Make sure scripts are included only once.
13) Configure Etags
Reconfigure or remove ETags.
14) Make Ajax Cacheable
Make sure your Ajax requests follow the performance guidelines, especially having a far future Expires header.
I highly recommend this book if you would like to improve the performance of your website. For detailed explanation and examples of those rules, please see: http://stevesouders.com/hpws/rules.php.