On social media, privacy is no longer a personal choice
Social networks can make predictions about people, based on information from their friends

When you share your contact list to a social network, that information can be used to infer information about your friends, even if they aren’t on social media at all.
peterhowell/iStockphoto
This article is only available to Science News subscribers.
Subscribers, enter your e-mail address to access our archives.
