Quotes of the Day

At one point in The Social Network, Aaron Sorkin's screenplay has Facebook creator Mark Zuckerberg getting testy with his less visionary co-founder. "We don't even know what it is yet," the Hollywood version of Zuck says of the fledgling service, whose membership has skyrocketed to 4,000 Harvard students. "We don't know what it is, what it can be, what it will be."

I'm not sure whether the real-world Zuckerberg has ever put it quite that way, but half a billion members later, that snippet of dialogue neatly sums up Facebook. The service remains in continuous reinvention mode, and it's surprisingly unabashed about taking steps that may confuse and/or tick off its users.

That was true earlier this year when it made sudden, sweeping changes to privacy settings that had some members up in arms. (A few weeks later, it tried to mollify unhappy campers with further tweaks.) It was also the case last week, when it introduced Groups, a feature that lets anyone construct a small social network — a sort of Facebook within Facebook. Weirdly, people who set up Groups can add their friends as members without asking first, and the default setting automatically e-mails activity updates to everybody — adding a pointlessly spammy aspect to an otherwise fine idea.

All the unpleasant scrutiny surrounding the site begs an important question: Is Facebook worth the occasional headache? I think so. And I have some thoughts — philosophical as much as tip-oriented — about making it work for you.

1. Stay Public or Go Private
In days of yore, only your Facebook friends could see most of your activities on the service unless you explicitly requested otherwise. Lately, though, Zuckerberg has decided that Facebook's "default is social" — which is another way of saying that the service errs on the side of showing your postings, photo uploads and other activities to all members, not just your friends.

You, of course, may prefer to maintain a lower profile. Go to privacy settings in the account menu in the upper right-hand corner to see how widely Facebook shares your information and to make changes — which you can do either in one comprehensive step or category by category.

2. Don't Set It and Forget It
Facebook's privacy settings are just the beginning of its customization options. You could devote a long weekend to burrowing through the possibilities for adjusting everything from e-mail notifications to the behavior of third-party applications (both on Facebook and elsewhere) that meld with the service in one way or another. All these options hang off the account menu on the upper right-hand side of Facebook's interface.

Because Facebook is a work in progress, fiddling with its settings isn't a onetime project: as new features get introduced, you should verify that they're configured to behave as you wish. For instance, the default setting for the recently introduced Places — which lets you use your phone to announce that you are visiting or "checking into" a local establishment, à la Foursquare — allows your friends to check you into a venue, no permission required. I know plenty of folks who want to decide for themselves whether their location gets broadcast or not.

3. If You Must Embarrass Yourself, Do It Offline
On some level, Facebook's privacy settings are misnamed: privacy is never guaranteed when you share information, opinions and photos on a service with 500 million members. Even if Zuckerberg and company have learned once and for all that it's a lousy idea to flip default settings from private to public, it's awfully easy to misunderstand features and share items more widely than you intended. There's also nothing stopping friends from copying your photos or status updates and redistributing them.

Consequently, it makes sense to maintain a certain level of decorum on Facebook. Don't be a ranting jackass, don't upload photos of yourself engaging in drunken revelry, don't share details about your life that you'd prefer stay confidential. I understand that this advice is easier to follow if you're a 46-year-old claims adjuster than a 19-year-old college sophomore, but I still think it's the right approach for Facebookers of all ages and predilections.

4. Choose Your Friends Carefully
On Facebook, as in life, the definition of friend is fungible. You get to decide whose friendship to accept or deny, and whether you want to precisely replicate your existing social ties or rack up a count that would leave Dale Carnegie seething with jealousy. The bigger your network, the more overwhelming and impersonal Facebook can feel. Also, you might not want to share heartfelt missives with people you barely know, or to be subjected to their FarmVille alerts.

I'm not contending that an ultra-picky approach is right for everybody — I have 1,739 Facebook buddies myself. (Then again, I've let 108 souls who want to friend me sit in limbo, mostly because I have no idea who they are.) But if you're trying to keep things simple, maiden aunts and lifelong best friends are far less likely to cause trouble than random almost strangers.

Related tip: It's entirely permissible to prune your list periodically, refining it down to the people you really care about. (Those you unfriend won't get a notification that you've purged them.)

5. Feel Free to Opt Out — Temporarily or Forever
Unlike death and taxes, Facebook is voluntary. You can deactivate your account, which lets you return later and pick up where you left off, or simply blow it away. Also, starting this month, you can download everything you've ever contributed into one humongous compressed file, letting you take your memories with you when you go.

Some of the smartest people I know choose to stay off the Facebook grid. They find the concept fundamentally unappealing, they have tried it and didn't like it, or they are simply oblivious. On the whole, they don't seem like an unhappy lot, and with more than 6 billion human beings not (yet) on the service, they've got plenty of company. If you choose to join them, there's no need to apologize — and if the service isn't working for you, there's no reason to stick around.

McCracken blogs about personal technology at Technologizer, which he founded in 2008 after nearly two decades as a tech journalist. His column for TIME.com, also called Technologizer, appears every Tuesday.

• Harry McCracken
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