The CEO of a major technology company once famously opined that, in the Internet Age, “You have zero privacy. Get over it.”

Some of us would rather not. We’d like to keep our personal information – whether it be what we share with friends on Facebook or our credit card details – under some control. We’d prefer not to let such information out into the wild, where it can be bought and sold and, often, used against us.

If you, too, are a privacy traditionalist, take heart: there are things you can do to make browsing, shopping, socialising, and other online activities less of a threat. That CEO was right in some ways: we probably can’t keep all of our private information private. But we can certainly make accessing it harder for those who’d like to make it public.

Your private profile

The risk  Since the entire goal of social networking is to help you connect and communicate with other people, the privacy settings on most social networks default to Wide Open. They often stay that way, because many users don’t know how to adjust them.

How to protect yourself The ease with which you can customise privacy settings varies by service. Twitter has one option: on your Settings page, you can select your Tweet Privacy to protect your tweets (meaning that only people you approve can see them). At the other end of the spectrum are services like LinkedIn, which scatters its privacy settings across nine screens, and Facebook, whose supposedly simplified privacy settings span menus up to four layers deep.

No matter which service you use, it’s incumbent on you to find out where these settings live (Google is your friend in that regard). Once you find them, the most important settings to look for concern:
• Who can see your posts and activities.
• What information is shared with external sites and businesses.
• Which applications can access your data.
• What information your friends can share about you.
• Who can see your pictures and/or location.
• Which sites integrate with your social network (for example, those that link with Facebook’s Like feature).

Most services allow you to adjust privacy settings in these categories: friends (or immediate contacts); friends of friends (or second-degree contacts); third parties; or everyone in the world.

On Facebook, be sure to control what your friends can share about you (under the hard-to-find Account > Privacy Settings > Apps And Websites > Info Accessible Through Your Friends), because that could override other settings. Also, keep an eye out for changes in the service’s privacy policies, and adjust your settings accordingly.

Finally, consider what you put in your profile in the first place. There’s no rule that you have to provide all the information for which there’s a field. If you don’t want everyone to know how old you are, don’t fill in that birthday field. It’s possible to provide virtually no private information yet still use the service.

Public profile

The risk Most services show the world a public profile, one that’s different from the one your network can see. But that public profile can still include some private information.

How to protect yourself Review your profile and see what information is public. Check your settings, then log out and look at your profile.

External applications

The risk With your approval, most social networks allow access from external applications, third-party games, and third-party sites such as Twitter. Some of these apps require complete access to your account, including ongoing access to all of your activities, perhaps even your friends’ information.

How to protect yourself Depending on the service and application, you may be able to control what such applications can access. Do you really need to give that snowball app access to all your photos and posts?

Your friends and you

The risk You and your friends can be the biggest threat to your privacy. They may accidentally reveal information about you by tweeting, posting, or updating without considering the consequences.

How to protect yourself The first rule of social networking: assume that everything you post is public and accessible to anyone forever. These networks are great for sharing and connecting, not so great for private communication. So think before you post. Leave Twitter and Facebook alone when you’re skipping work for a happy hour that the boss wasn’t invited to.