Google's plans for using personalization to improve search results could face some difficulties. Google already uses your queries, the results you click on, your bookmarks, but this isn't enough to build a comprehensive profile. People don't search too many times and, most often, they click on the top search results.
So I think the next step in Google's efforts to tailor the search results to your preferences is to expand the search history into something more complex: the web history. Browsing web pages is an important part of your online activity and there are already applications like Google Desktop that monitor and index the visited web pages.
Google Web History is a reality starting today. This replaces the previous search history service that was limited only to queries and search results. If you want to add the web pages you visit, you need to have Google Toolbar with the PageRank feature activated and to enable web history here. It's just the regular toolbar, but you'll have to explicitly allow Google to use the PageRank feature to record all the visited web pages and associate them with your Google Account.
The listing mixes visited web pages with Google searches, as you can see in the screenshot below:
"You know that great web site you saw online and now can't find? From now on, you can. With Web History, you can view and search across the full text of the pages you've visited, including Google searches, web pages, images, videos and news stories."
Besides keeping track of all the web pages you visit and making them searchable online, Google Web History is used to improve the personalized search results.
"Web History uses the information from your web history or other information you provide us to improve your Google search experience, such as improving the quality of your search results and providing recommendations."
Google says they encrypt all the data and you're the only one who can access it (they even ask your password multiple times during a session). Web history is a feature implemented in most modern browsers, but the storage is limited and the history is usually deleted after a small number of days. Google's new feature lets you store your entire web history online (and that sounds pretty scary).
Of course, you can pause the service at any time and even delete the entire web history, but the big question is: do you trust Google enough to send it all your online activity?
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