The kind you don't ask your best friends. The questions are reflected in the autocomplete. You can do the test yourself. Enter "Is my husband gay" and you will see "Is my husband gay?" at the top of the list of search results. So this is googled particularly frequently by women. Aha!

• Parents google "son gifted" two and a half times more often than the same for their daughter.
• Parents want to know whether girls are overweight twice as often as boys.
• Porn is searched for more often than the weather.
• The most common sex question from men is how to last longer in bed.
• While men often look for penis enlargement, 40 percent of women's searches about penis size are about it being too big.
• The most common concern women have about their partner's orgasm is why he doesn't come at all.

3 questions for the expert

How anonymous is the internet? What does Google know about us? We asked Professor Chris Brzuska from the Institute for IT Security Analysis at the University of Hamburg. If you want to know what Google has stored about you, you need a Google account. You can view the data at www.google.com/dashboard

Mr. Brzuska, what does Google know about its users?

"If we use Gmail for email, Google Maps to search for directions and the search engine to answer our questions, and possibly all on the same smartphone, then Google gets an accurate picture of us."

Are all data and search entries really saved?

"Almost all of them. Google's service model is based on collecting and evaluating comprehensive data in order to optimize services for users."

What happens to user data, for example?

"User data is brought together. Google also reflects social stereotypes, as you can see in the autocomplete function."