Immigrants from Pakistan to New Jersey often join an existing community that helps them to integrate, she explains, whereas "refugees, especially refugees from war-torn areas like Somalia, have a very different kind of assimilation process".

BBC: American jihad: Facing up to homegrown militancy

Part 1, How Tumblr Drove the Evolution of Content into an Image Dominated Experience, illustrates how the assimilation of Facebook into lives of modern web users established a basic fluency with the content creation process.

FORBES: How Tumblr Drove the Evolution of Content into an Image Dominated Experience