Not sure what you mean by "layered". <br /> Firefox is based on Gecko ''(originally created by Netscape)'', where Google is based on WebKit which was created by Apple. Chrome has more in common with Safari, than with Firefox. http://en.wikipedia.org/wiki/Gecko_%28layout_engine%29 <br /> http://en.wikipedia.org/wiki/WebKit As far as what they have in common, they both use Google search for the default search engine (in Firefox that can be easily changed though) and both use the same anti-phishing / web forgery protection that was jointly developed by the two organizations back in 2005 - 2006 before the first Chrome alpha-version was available to anyone outside of Google. From the little I have read about the new Google privacy policy, it looks like if you don't log into any Google services nothing of any consequence is going to be any different than now. My advice is to be patient and wait for some of the internet security experts analyze the changes this coming week and see what they recommend.

How do I easily change the default search engine?