1. Google know what you search:
They keep track of everything you search. They used this in their Adwords program.
2. Google Knows What Videos You Watch:
They use this information to recommend you videos on YouTube.
3. Google knows every webpage you visit:
If you use Google Chrome internet browser, every page you view in that browser can be shared with Google. Google has confirmed that they do not use this information to display ads on your computer.
4. Google may know when you’re going to be sick:
If you search for illnesses using Google search, it is being recorded by Google. For example, if you search up keywords relating to how to cure a flu illness, Google keeps track of that. It is rumored they use that information to keep track of where illnesses start and where they are spreading to, and they can estimate when a virus will reach a certain area.
5. Even if you don’t use Google Chrome, Google may still know what websites you visit:
A lot of websites have ads on their site displayed by Google. If you are part of the Adsense program there is an area that shows how many people have viewed your ads. Google keeps track of what sites ads are displayed to you on.
6. Your medical information may be shared with Google
If you have ever used Google Health, anything you have submitted there may be being shared with Google. How or if they even use this information is not known at all.
7. Google knows the popularity of your website:
If you have submitted your website to Google Analytics, information about your website such as traffic, amount of unique visitors, page view, and how people find your site is being shared with Google.