Facebook CEO Mark Zuckerberg shows Timeline during the f8 conference in San Francisco, Thursday, Sept. 22, 2011.(AP Photo-Paul Sakuma)

Facebook CEO Mark Zuckerberg shows Timeline during the f/8 conference in San Francisco, Thursday, Sept. 22, 2011.

Soon Facebook users who have been avoiding the social network’s Timeline feature won’t be able to stave it off any longer and will be seeing their profiles change considerably. That’s because Facebook is making Timeline compulsory and is rolling it out to users in the next couple of weeks.

You should be aware of several things before the launch. Here's how to prepare.

Are Your Posts Viewable by Strangers?

Instead of a linear stream of your posts, the new Timeline is a visual aggregation of everything you’ve ever done on the site: the information you’ve included on your profile, your photos, everything you’ve ever “liked,” any Facebook apps you’re using, a map showing where you’ve been (according to geo-tagged posts and photos), as well as a Timeline of everything you’ve ever posted.

The problem is that Facebook seems bent on making all of that data more public. Now any post that you make defaults to Public, so if you forget to choose “friends” in the inline audience selector when you post something, the entire world can see it.

That’s why it’s very important that you check out how your Timeline looks when other people view it. You may find that many of the posts you intended for your friends are public.

To see how your Timeline looks to strangers, click on the small gear just below the right corner of your cover (the spot where you can place a large banner photo at the top of your Timeline). From the gear, click View As. From there, you’ll be able to preview your public Timeline.

To make sure your past posts are limited to friends, click on the small arrow on the top right corner of your Timeline. Then go to Privacy Settings Limit the Audience for Past PostsManage Past Post Visibility and select Limit Old Posts. Alternately, you can change the audience by clicking on the small pencil icon at the top right of individual posts to edit or hide them from the Timeline.

Once you get Timeline you only have seven days to make changes to it, such as hiding old posts from years ago that you may not want the world to see, or managing the visibility of your posts.

So if you’re someone who doesn’t check into Facebook often, you might want to proactively get Timeline now and then sit down to review it and make changes.

Several privacy groups are urging the Federal Trade Commission to look into whether Facebook oversteps its authority with Timeline, but in the meantime, it's up to you to check your privacy settings.

Facebook Wants More of Your Data

Another thing that the new feature lets you do is add events from any part of your past -- all the way back to birth, if you want -- to create an online scrapbook of your entire life.

If you’re not sure what kinds of things you should add, Facebook has plenty of ideas. Inside your Timeline you can click on Life Event in your status bar and you’ll be asked to categorize your entry into one of these headings: Work & Education, Family & Relationships, Home & Living, Health & Wellness or Travel & Experiences.

Within each category is a slew of suggestions. For instance, under Home & Living, you can choose: Moved, Bought a Home, Home Improvement, New Roommate, New Vehicle and Other Life Event.

Can you imagine all the new data Facebook is going to be accumulating from users? The reason, of course, is to laser target ads at people. But some people don’t like the idea of Facebook having such rich profiles about individual users on file.

Some Security Concerns

Security firm Sophos polled 4000 Facebook users, asking them what they think of the new Timeline and the response was overwhelmingly negative, with 51 percent saying the feature worries them and another 32 percent saying they don’t know why they’re still on Facebook.

For one thing, with more of your data possibly accessible by strangers, it may be easier for criminals to profile people and glean personal information.

The reality is that personal data is very valuable to criminals.  For example, with enough information a bad guy can impersonate someone in order to do things like pull off phishing scams. 

In its Naked Security blog, Sophos points out that once they see all their data clumped in one place many Facebook users are shocked at how much information about themselves they’ve posted online.

Another thing that might make you uncomfortable is the map included in Timeline that shows where you hang out. If you don’t want people seeing that information, make sure to go back to any geo-tagged posts or photos and either change the location or hide it from the Timeline.

Timeline Fans Exist, Too

Not everybody is going into paranoid mode with the rollout of Timeline and some people really like it.

PCWorld’s Jared Newman believes that in time, Facebook users will come to like Timeline. The downside, he points out, is that users must do some cultivating to bring their most relevant life details to the surface.

Follow Christina on Twitter and Google+ for even more tech news and commentary and follow Today@PCWorld on Twitter, too.

Copyright (c) 2012 PCWorld Communications, Inc.

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