5. Do I Know You?
Facebook started out as a way for college students to put faces to names: "Hi, I think we took Poly Sci together last semester, and you're friends with my friend Brittany. Would you be my Facebook friend?" Now that Facebook is a global phenomenon, exchanges can go more like this: "I don't know you, and we have no friends in common. I live in Colorado, you live somewhere far away. And yet you'd like to be my friend and show me your baby pictures. And you want to see mine. Hmmm, let me think about that ... request denied." Not only is it okay to ignore friend requests from people you don't know, your privacy may depend on it.

4. Thanks for the Add! Here's Some Spam
Slightly more annoying than random friend requests from total strangers is the increasing presence at social networking sites of good old-fashioned spam--you know, the kind where somebody is actually trying to sell you something. On Facebook, MySpace, and many other sites, you can expect to receive all kinds of unsolicited commercial and noncommercial requests, promos, and e-mail messages in your inbox. All manner of enterprises, from fledgling rock bands to escort services to professional headhunters, are trying to use these newfangled social network things to drum up business, and that means spam.

3. Breaking Up Is Hard to Do (Too Hard)
Late last year I realized that I'd read one too many inspirational peace, true love, and happiness-through-vegetarianism bulletin posts from some random friend on MySpace, and I decided that I'd had enough. I decided to cancel my account. I wanted to disappear from the scene--to commit "MySpace Suicide." But I quickly found out that it wasn't as easy as clicking a Delete Account button. Perhaps to protect accounts from unauthorized deletion, some services require you to send a formal cancellation request--LinkedIn requires you to contact customer service, for example. MySpace does let you delete your own account, but only if you still have access to the e-mail account you used to set it up. Unlucky for me, I had changed ISPs during my two years of MySpace membership, and I no longer had my old e-mail address. So began a four-week account-cancellation process, culminating in my actually having to e-mail MySpace a picture of me holding a piece of paper with my MySpace user name scrawled on it. I might have been better off just leaving the account active and deleting all the data and content it held.

2. Zombies, Pirates, and Other Pointless Facebook Applications
Facebook applications allow my friends to share their movie tastes, opinions, news picks, and other items with me, but accepting these tidbits requires me to install each corresponding app in my own profile (at which point it has access to my personal information). One app informs me that a friend has just urinated on me, poked me, or vampire-bit me. An alarming number of my female friends want me to know them by their stripper names. Why my friends devote so much time to these curious little apps I haven't figured out, but I know that cumulatively they've begun to demand way too much of my time.

To make matters worse, Facebook applications promote themselves, too, trying to get in touch, and even peppering me with spam. If you're encountering the same thing, you can fight back. To make silly apps go away, open the application invitation and click on the Block [application name] link in the bottom-right part of the window. Or, you can banish all applications from your Facebook experience by installing the Facebook custom app hider Greasemonkey script.