A few best practices for web page performance

1.Make Fewer HTTP Requests

2.Use a Content Delivery Network

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

15.Flush the Buffer Early

16.Use GET for AJAX Requests

17.Post-load Components

18.Preload Components

19.Reduce the Number of DOM Elements

20.Split Components Across Domains

22.Minimize the Number of iframes

23.No 404s

24.Reduce Cookie Size

25.Use Cookie-free Domains for Components

26.Minimize DOM Access

27.Develop Smart Event Handlers

28.Choose <link> over @import

29.Avoid Filters

30.Optimize Images

31.Optimize CSS Sprites

32.Don’t Scale Images in HTML

33.Make favicon.ico Small and Cacheable

34.Keep Components under 25K

35.Pack Components into a Multipart Document

Source : Yahoo Developer Newtwrok

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