With the growth of social networks at the turn of the century, individual identities became fragmented across networks. As those networks proliferated, people have begun to talk about mesh-to-mesh identity--or M2M identity.
A person's identity tends to vary across his or her differing social networks (or meshes); M2M identity has thus become shorthand for talking about all the ways people present themselves and all the tools and processes that they use to bridge the divergent selves across distinctive networks. It's a catchall phrase for identities that are constantly shifting as people are shaped by changes at the edes of their networks--edges they may not ever actually interact with directly. People who fully engage with their M2M identities often go for extreme social transparency, an open-access version of the "quantified self" that Kevin Kelly began documenting in 2008.