Danah Boyd post on Pew's report on report on Social, Media, and Privacy and she closes with this paragraph.
Over the last few years, I’ve watched as teens have given up on controlling access to content. It’s too hard, too frustrating, and technology simply can’t fix the power issues. Instead, what they’ve been doing is focusing on controlling access to meaning. A comment might look like it means one thing, when in fact it means something quite different. By cloaking their accessible content, teens reclaim power over those who they know who are surveilling them. This practice is still only really emerging en masse, so I was delighted that Pew could put numbers to it. I should note that, as Instagram grows, I’m seeing more and more of this. A picture of a donut may not be about a donut. While adults worry about how teens’ demographic data might be used, teens are becoming much more savvy at finding ways to encode their content and achieve privacy in public.
This technique of cloaking is not anything new. The Chinese micro bloggers have learned to use this method to say things that don't trip censorship filters.
Pew report says
Other privacy protecting and obscuring behaviors
Many teen social media users will make the content they share more private by obscuring some of their updates and posts, sharing inside jokes and other coded messages that only certain friends will understand; 58% of teen social media users say they share inside jokes or cloak their messages in some way.45 Older teens are considerably more likely than younger teens to say that they share inside jokes and coded messages that only some of their friends understand (62% vs. 46%). Girls and boys are equally likely to post inside jokes and coded messages, as are teens across all socioeconomic groups
In the data center world this is no different than inside jokes.
An in-joke, also known as an inside joke or in joke, is a joke whose humour is clear only to people who are in a particular social group, occupation, or other community of common understanding. It is an esoteric joke which is humorous only to those who know the situation behind it.
In-jokes may exist within a small social clique, such as a group of friends, or extend to an entire profession such as the film or professional wrestling industries, or a particular sporting endeavour. Even an ethnic or religious group may have its own in-jokes.
I often use this same cloaking technique as I can say things to a specific set of readers that to others just looks like a regular blog post. :-)