Google might have a complete list of almost everything you’ve ever looked at.

The list can be quite helpful. All of the information is completely searchable, so if you remember just one part of a website’s name or only the day you visited it, for instance, you can find it back out again.

Google collects the information in part so that it can be useful to you – jogging your memory, helping you find past websites, and learning more about you so that it can recommend more relevant things. But it is mostly so that Google can use that information for its ads, learning what you’re into and what marketing is most likely to appeal.

So if that makes you worry, it’s easy to turn the collection off. (You’ll still get ads, they’ll just be more generic.) That’s done by heading to the Activity Controls page, and turning off the data collection.

The page is similar to Google’s audio history page, which collects the recordings that your phone makes of you. Like the search results, the recordings are supposed to be useful – but you can easily stop them being stored from the same page.

Google also keeps information on where its users have been. That too can be viewed on a handy timeline at the location history page, where it can also be turned off and deleted.