Google will still keep some of your Web history information regardless of your settings, but the results won’t be used to customize your search results. According to Google, the company “also maintains a separate logs system for auditing purposes and to help us improve the quality of our services for users.” Google keeps the information to “audit our ads systems, understand which features are most popular to users, improve the quality of our search results, and help us combat vulnerabilities such as denial of service attacks.”

Note that if you want to delete your Google Web history from your computer, you should also clear it in your browser and from any Google toolbars you may have. To do so, head to your browser’s search history settings. In Firefox and Internet Explorer, you can clear history from the “Tools” menu. In Chrome, click on the wrench icon, head to the “Under the Hood” tab and choose the “Clear Browsing Data” option.

To delete all or part of your Google account (your profile, say, or your Google+ account), you can use the same “Services” area of your “Account Settings” panel.

If you don’t want to delete any data but just want to start new, more privacy-friendly search habits, there are a few tips. For one, you could opt for a different search engine from time to time, which will thin out Google’s data profile. You could also try using private browsing modes, which are available in each of the major browsers. Web sites you visit while using Chrome’s “Incognito Mode,” for example, won’t show up in your browsing or download histories. Using this mode will also clear any cookies you may have picked up during your session, though changes you make to your bookmarks and general settings will stick no matter what.

The Electronic Frontier Foundation suggests that those who want to protect their search privacy more generally steer clear of conducting searches for their own private information (name, address, etc.) and avoid using your Internet service provider’s search engine.