"The trouble with Google Chrome's incognito mode is actually down at least in part to Google's own desire to store information about users' surfing habits - it uses this kind of information not only to improve its own searching algorithms but also sell more targeted advertising opportunities to advertisers.
So it seems that if you sign into your Google Account on http://www.google.com while in incognito mode, your subsequent web searches are recorded in your Google Web History. That might not seem so bad, except that it may be that more than one person in your household shares a single Google Account, potentially making your web surfing rather less than 'incognito'. "
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