Don't go looking for Google+ History. Right now, it's available only to developers so they can support it with their software. Google will make it available to users later.
In a nutshell, Google+ History will make it possible for third-party apps, sites and services to share information about your online activities with Google+. For example, if you post on Twitter, a copy of your tweet will show up in your Google+ profile.
Google+ History doesn't actually share content from the other sites with your friends. Instead, it places it in a secure, private space on Google+ where you -- and only you -- can see it.
If you would like to share any of these items, you have to explicitly take action to do so.
In my opinion, this is how social sharing should work.
Using Google+ History
Details about Google+ History are hard to come by. But it's pretty clear what Google hopes to accomplish.
Right now, Google+ History exists only in the form of an API, a programming interface that enables software components to interact and connect, and as a preview for developers for testing their software.
Google+ History is functionally similar to Google's Instant Upload feature, which automatically uploads pictures you take with your phone to your Google+ profile without sharing them with anyone but you.
When you create a post, you may choose to include any of the phone pictures that have been uploaded via Instant Upload. Or you can ignore them.
In fact, it's helpful to think about Google+ History as an expansion of Instant Uploads -- it expands the types of content that can be "instantly uploaded" and makes "instant upload" functionality available to companies beyond Google.
The magic feature of both Instant Uploads and Google+ History is the instant and automatic uploading of content that is not shared until the user deliberately shares it.
In other words, it doesn't share content for you -- it locks and loads it for you. The content gets shared only if you take action to share it.
Here's how I think users will experience Google+ history.
As third-party websites, online services and mobile apps increasingly support Google+ History, they'll add Google+ to the list of options for sharing what happens on their services. If you agree and choose to authenticate Google+, everything -- or some things -- you do on that service will show up on your Google+ profile, but only where you can see it and nobody else can.
Let's say you use Foursquare and read your favorite tech publication -- the one you're reading now. And let's also say you authenticate these services with Google+ History.
It's Saturday morning. You go to a Starbucks and check in on Foursquare. Then you use your tablet to read an article like the one you're reading now. You're fascinated by this brilliant Mike Elgan guy, and you want to tell your friends on Google+.
So you fire up Google+ and there already waiting for you are both actions, which Google calls "moments": The check-in and the article.
These are sitting on top of an incredibly long list of past "moments" from the apps you've authenticated to work with Google+ History.
Instead of opening a blank window to write a post, you simply choose "Share" from a drop-down menu on the article "moment."
Google+ History will put a thumbnail photo from the originating site, plus a link to that content and a summary. In other words, it will build the basic Google+ post for you. Then you can write an additional sentence or two and click a button to share it.
Of course, you'll choose not to share the Starbucks check-in from Foursquare because, really, who gives a flying frappuccino that you were at Starbucks?
Why 'friction' is good
Google+ History sounds great because it essentially guesses what you might want to post, creates the posts for you with more and better details than you might add to a post yourself, and presents the posts, ready to go, in case you want to share them.
In other words, it makes certain types of Google+ posts better, and it gives you a quick and easy way to share them.
Also: The unpublished, unfiltered version of your "History" provides you with an amazing, ongoing but private record of your life. If you authenticate enough services, you could end up with an incredible "lifestream" of all your activity, even if you never share any of it.
The Google+ History API is the kinder, gentler alternative to Facebook's Open Graph API.
To oversimplify the difference between these APIs: Facebook's Open Graph enables any app or service to post content to a user's Facebook profile (with one-time permission by the user), while Google+ History enables those services to prepare content to be posted, should the user choose to do so.
Facebook's "frictionless sharing" idea via the Open Graph API involves social apps that automatically inform family and friends when you read something, listen to a song or take some other action.
Users are often embarrassed or humiliated by "frictionless sharing," as they broadcast to everyone that they've read some prurient article or watched some racy video or worse -- say, listened to a Justin Bieber song. This can go on for weeks, until someone awkwardly points out what they've been "sharing."
A friend of mine on Google+ shared a screen capture of a Facebook post that reported that another friend of hers had watched explicit pornography -- the application he viewed it in used Facebook's "frictionless sharing" to broadcast the details to his mother, his friends, his co-workers, his boss ... everybody.
At the Google I/O 2012 developers conference this week, Google+ vice president Bradley Horowitz said: Automated posts "don't really work." And he's right.
The reason is that they create an incentive for third-party social sites to game the system and aggressively exploit the users. Many don't, but the incentive is there.
It pits social sites against one another in a competition to see which can use Facebook's API to virally gain the most users. Whichever app can shamelessly entice the most people to sign up wins, even at the expense of the users' reputations.
Sites share tempting content with a user's Facebook friends. But the friends can't see it or watch it unless they, too, sign up to automatically spam their friends with tempting content.
So here's a prediction: I think Facebook will copy Google's approach to auto-sharing content. It will at some point add friction to "frictionless sharing" and close its "Open Graph" a little bit so that users must consciously choose to share third-party app activity before releasing such information into the social stream.
Why will Facebook copy Google+ History? For the same reason Facebook copied the Google+ Circle concept, the Subscription concept, the longer post size concept, the look and feel of Google+'s photographs, the ability to edit comments: They are better ideas.
Whether Facebook copies Google's latest offering or not, I'm really looking forward to Google+ History.
It's still early, but from what I can tell, Google+ History should improve my posts, improve the posts of the people I circle, and most of all, do it all while improving user control over what gets shared.
Who knows? It might even improve Facebook.
Mike Elgan writes about technology and tech culture. You can contact Mike and learn more about him at Elgan.com, or subscribe to his free email newsletter, Mike's List. You can also see more articles by Mike Elgan on Computerworld.com.
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