You'll learn how to optimize CSS declarations, how to optimize JavaScript code and avoid memory leaks, how to use the best image format and prefetch resources.
Google also released a Firebug plug-in for Firefox that evaluates web pages and provides suggestions to improve them. Here are the suggestions provided for this blog's homepage:
* There is 58.8kB worth of JavaScript. Minifying could save 15.7kB (26.7% reduction). Google provides the minified versions of all the inline blocks and external files.
* The following cacheable resources have a short freshness lifetime. Specify an expiration at least one month in the future for the following resources: [list of resources].
* The following domains only serve one resource each. If possible, avoid the extra DNS lookups by serving these resources from existing domains.
* An inline script block was found in the head between an external CSS file and another resource. To allow parallel downloading, move the inline script before the external CSS file, or after the next resource.
* A width and height should be specified for all images in order to speed up page display.
* Serve the following static resources from a domain that doesn't set cookies: [list of resources].