- 18 Feb 09, 09:45 GMT
So Mark Zuckerberg, the founder and boss of Facebook, has had to learn the hard way that a social network is nothing like e-mail.
In his original attempt to defuse a growing row over changes to its terms of service, Zuckerberg had tried to explain the decision to hold on to people's data, even if they quit the social network, by likening it to e-mail.
He said: "When a person shares something like a message with a friend, two copies of that information are created - one in the person's sent messages box and the other in their friend's inbox. Even if the person deactivates their account, their friend still has a copy of that message. We think this is the right way for Facebook to work, and it is consistent with how other services like e-mail work. One of the reasons we updated our terms was to make this more clear."
But users clearly have different expectations about their data when it comes to e-mail.
Users have come to accept and understand that e-mail takes on a persistent state when it leaves an outbox and flies across mail servers to reach the intended recipient.
On countless occasions retrieved e-mails have helped expose fraud or duplicity. And that's because e-mail is copied and copied again as it makes its journey to the intended recipient.
On a social network, users have a different notion of ownership of information. By signing up to a walled garden like Facebook, it is only natural perhaps that people feel the data that is stored on the social network remains their property.
From comments, to videos, photos and applications - this data remains sealed inside the Facebook garden regardless of whether it is sitting on a friend's Wall, or is a photo that can only be seen by members of a specific Facebook Group.
Unlike the web in general, where the spiders of search engines never sleep and crawl our data on public sites 24/7, making it available to all, Facebook is a private members club, in which each member decides who can and who cannot see or share their information.
What's so surprising about this row is perhaps how naive Facebook would appear to have been.
After all, users have long complained about how difficult it is to actually delete their accounts on the social network.
And terms of service for sites in general have always been a contentious issue. From Twitter rows to Google Chrome complaints and global data privacy debates, web firms have been wrangling with these issues for years.
And by flip-flopping between defending the new terms of service and reverting back to the old agreement while encouraging user feedback, Facebook is clearly one of many companies that have yet to fully resolve these issues.
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