Though it began in 2004 as an online yearbook for Harvard students, Facebook soon opened its membership to other universities, then high schools, then everyone else. You can search for friends according to their school, city, or work affiliations, and you can join more than one of these networks, allowing you to maintain connections with ex-classmates, neighbors, and coworkers. Using this approach, the site has grown to a staggering 60 million members. Its main features--photo and video sharing, messaging, and public message boards--are similar to those on MySpace, but it eschews the crazy skins and music players that render many MySpace profiles illegible.
Unfortunately, beneath Facebook's clean, blue-and-white facade lies potential risk. Last year, Facebook's controversial Beacon advertising scheme, which made members' online purchases viewable by other members, caused an uproar as members objected to being transformed into unwitting (and uncompensated) product endorsers. If you (reasonably) worry that such a privacy gaffe could recur, you can use Facebook's fine-grained security settings to establish an appropriate level of privacy protection. See "Give Your Facebook Page a Much-Needed Lift" from our December 2007 issue for additional Facebook safety and customization tips.
Unlike Facebook and MySpace, which are essentially about fun and friends, LinkedIn promotes your career or your business. LinkedIn has become one of the most talked-about social networks, and has quickly grown to nearly 20 million members.
Like other social networks, LinkedIn revolves around your personal profile. But instead of displaying lists of your favorite bands and collections of party snapshots, your LinkedIn profile showcases your employment history, your professional skills, and your education and awards, and explains how and why you want to be contacted. To get the most out of your LinkedIn membership, you should make these entries brief, complete, and sparkling, just as you would on any r
Is Twitter really a social network? Yes, but not in the way Facebook and MySpace are. The content that drives Twitter is a relentless stream of real-time personal status postings called tweets, each limited to a maximum of 140 characters. "Going out for more batteries," or "Feeling snacky, I think I'll have a salad" are the stuff of Twitter greatness--as long as tracking your friends' ephemeral actions and mutterings is your cup of tea.
After you've signed up, it's worthwhile to peruse the ever-changing public updates page--to see the variety of ways people use Twitter and to find interesting Twitterers to follow. You can also allow Twitter to search through your e-mail address book to see whether any of your contacts are already Twitter users. In time, other people may follow your tweets, too. If you'd rather not broadcast your posts to the universe, select the 'Protect my Updates' option in Twitter's settings to keep your posts out of the public timeline and approve any followers before they can see your tweets. You can even have Twitter "nudge" you with an e-mail reminder should you forget to post for a while. When you're away from your computer, Twitter permits you to send and receive tweets on your cell phone via SMS or Twitter's mobile Web site. I recently used the latter to keep tabs on Steve Jobs's January Macworld Expo keynote via the twittering of several Mac pundits in the audience.