How do you define "social media" ?

Is youTube social media?

What about bugguide.net?

Is LinkedIN?

Minecraft?

Email?

I do think a definition is possible. Social media are online applications that allow social interactions in a mix of public, and/or private groups and networks.

Email is not social media (though usenet might be)

Bugguide and minecraft have social media functions but are not primarily social applications.

LinkedIN is a cancer.