Who do you "friend" in social networks? Are they people you know "IRL"? Are they people you know well? Are they your friends -- I mean "really" your friends -- or is the relationship better described with some other word -- co-worker, perhaps. Co-worker's husband. Colleague. Associate. Former teacher. Mother-in-law. Someone you knew in elementary school.

I should be clear here: I would never imply that someone that you know solely via online interactions cannot be your friend. And likewise, I'd never suggest that simply because you've had years and years of face-to-face interactions with someone that that necessarily makes the two of you friends.

But as I've packed up my cubicle at work and as I've sent a lot of "let's stay in touch" emails to various co-workers and colleagues over the past few days, I couldn't help but think about friends, friendships, and the relationships we now cultivate via social networking. These thoughts were also prompted, in part, due to an article Sarah Perez wrote for ReadWriteWeb yesterday: "Location-Based Social Networks: Delightful, Dangerous or Somewhere in Between?"

As the title suggests, Sarah's post looks primarily at the increasing popularity of location-based social networks and the potential drawbacks to announcing one's whereabouts there. She asks "[I]s sharing your location with your online "friends" asking for trouble?" Although much of the anxiety around geo-social networking has centered on prviacy concerns, the other issue -- for me at least -- involves a different but equally important implication: how is social networking (location-based or otherwise) changing what we mean by the word "friend"? Sarah's use of scare-quotes around the word points to what I think we all know and -- begrudgingly or not, with some reflection or not -- accept: many of the people we allow into our networks are not our friends at all. Nevertheless many social networking sites reward us based on the number of friends we have. As Sarah observes, "Ever since the days of MySpace, it seems the goal has been to accumulate the most friends. This mindset has carried over to many other social networks, including FriendFeed and Google Buzz, all of which publicly track and expose how many people follow you, an indication of popularity...and who doesn't want to be popular?" Add to her list the incentives with most new social games to increase the size of one's network (and, more importantly, to increase the proportion of one's network also involved in the game), there is a huge push for us to expand our connections.

But the label that Facebook gives these relationships aside, a lot of these connections likely aren't your friends. And yet we find ourselves sharing information -- sometimes deeply personal information -- with these networks as though the folks who "follow" us there need or want to know, as though they should know.

Don't get me wrong: I love social networking, and I love the connections I have made online -- personally and professionally. I learn a lot every day from the folks I follow on Twitter and from the blogs I read, and yes, even from some of the links and comments I see on Facebook. But that's an intellectual connection -- and while I'm a geek and a writer and a thinker and a student and whatnot -- that intellectual connection does not necessarily a friendship make.

Sorry -- no hard feelings, ok? But hey listen, social-network "friend," the next time I'm in town, we should totally go for beers. Just find me on Foursquare, and we'll hook up, ok?

(Or not -- and you know what, it'll be fine. We're just (Facebook) friends after all.)