A new study has found that almost half of U.S. adults online don't understand where Facebook funds are coming from.

The study, conducted by by The Search Agency, surveyed 2,006 American Internet users. Of those surveyed, only 54% could say how Facebook earned cash — 57% of men and 51% of women.

So perhaps Facebook isn't being all that clear when it comes to its reliance on advertising.

SEE ALSO: Facebook Search Will Make Money, But Still Be Ineffective

The study also found that 22% of people polled have clicked on an ad via a search engine and that millennials were two times more likely than older users to click on search engine ads. Check out the video above to learn more about the study.

Were you ever confused about how Facebook turns a profit? Tell us in the comments below.

Via AllFacebook.com. Photo via iStockphoto, sd619.