What you need to know:
Search engines collect a variety of information from you which can include search queries, click through-histories, location data and internet browsing histories. In addition, this information can be combined with data collected from other services provided by these companies like email, news portals, web browsers, collaboration tools, payment systems and device offerings, among others. It can also combine it with data collected from other web and app partners, which when all combined creates comprehensive profiles of you.
For search engines, these data profiles are used for various reasons such as improving search quality, optimizing/personalizing search results for you and targeting advertising. The trade-off made by most consumers is the ability to use these services for free in exchange for detailed data on themselves, which these companies use to fuel their advertising engines. The more data search engines collect, the more targeted their advertising can be and the more advertisers are willing to pay them for it.
Privacy concerns are raised not only about the sheer amount of data that is collect by these companies, but also whose hands it can ultimately end up in. These companies do generally, indirectly (see the “Learn More” section), share some level of data with third party partners to enable advertising. In addition, the government has consistently requested and obtained data from search engines. Finally, as with any database this information can and has been susceptible to hackers.
Overview of search engine privacy considerations
What a study about Google data collection showed
Learn about never-Googlers
How Google “indirectly” shares your data for advertising
Google’s policy on sharing data with governments
Australia suing Google for misleading consumers on collection and use of personal data
What to do:
For Google, if you visit their privacy policies page, under “your privacy controls” you can: see your activity/data from their different services, see your “interests” according to them and export a copy of your content on Google.