What does it mean to be a “friend” these days? That’s a question many experts are struggling to answer, as Websites like Facebook continue to blur the line between the real friends we see face-to-face, and the virtual friends we may never meet. For example, Sherry Turkle is an MIT sociologist who thinks the word “friend” has lost its meaning entirely. That’s because we live in a world where preschoolers are taught to call everyone a “friend,” and where you can click a button on Facebook and make any stranger your “friend.” Turkle calls that “friendship on demand,” because it’s companionship when you need it, without all the tricky intimacy.

She adds that most people can’t even make up their mind what the word “friend” should mean. Think about it: Some older adults might tell you a true “friend” is someone you’ll do anything for. Others say “friends” are people you see occasionally, who you might hang out with after work. For many teenagers, “friends” can include people you chat with online - even if you never meet them. To make things more confusing, anthropologist Robin Dunbar says there’s a limit to how many real “friends” we can have: About 50. His thinking is that friendships require a certain amount of attention to grow – and our brains can only handle so much “emotional investment.” So it may be physically and mentally impossible for us to make time for more than a few dozen “real” friends in our lives.