For years, when new users joined Facebook, the default privacy setting had been to share your every baby photo/quote of the day/quiz result/divisive political rant with the public at large. Users had to opt into higher levels of privacy to limit their updates to smaller groups. But today Facebook announced that the default setting for new users is to only share posts with folks on their lists of friends.

“While some people want to post to everyone, others have told us that they are more comfortable sharing with a smaller group, like just their friends,” explains the company in its announcement of the change. “We recognize that it is much worse for someone to accidentally share with everyone when they actually meant to share just with friends, compared with the reverse.”

The first time a new user goes to post something on Facebook, he or she will be asked if they want to select a particular audience for whatever it is that is about to be posted. The user will have the option of going public, but the default is friends-only.

But what about the hundreds of millions of existing users who may not know that every person on Earth can read their every musing?

Facebook says it intends to address that concern with the rollout of a “new and expanded privacy checkup tool,” that it claims will guide users through a step-by-step review of their settings.

What people need to remember — especially if you post things you wouldn’t necessarily want your employer, family, potential mates, or the general public to see — is that just because something is set to “friends only” doesn’t mean that those friends are the only people who will ever see it.

All it takes is for one of those friends — a term that has all but lost its original meaning thanks to social media — to make a screengrab of whatever you post. Then it can be shared with everybody, and if it’s embarrassing enough, it probably will be.

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