Sure; unlike other services, we don't have display advertising. We have what we call our own promoted products, which are organic and integrated into the Twitter service. The different promoted products we have are promoted accounts, promoted tweets, and promoted trends. Those are all parts of the Twitter service, and we just have a component of them that's promoted. We show people our promoted products in the same way that we try to show them other content that we think they may be interested in.
For example, when you see suggestions for accounts for you to follow, we may show you a promoted account in connection with other accounts that are not promoted. In the same way that we were talking about earlier, we may suggest that you follow particular accounts because people you are already following have already followed those accounts; we might do the same thing with a promoted account.
For example, I follow a bunch of lawyers, a bunch of technology journalists, and some privacy researchers. These people may be following an account that is an upcoming privacy conference. Perhaps the privacy conference has decided to promote its account, given that the conference is coming up and they want more people to be aware of what's going on, so that might show up as a promoted account.