Moments of crisis, like the shooting in Newtown, tend to produce brief spikes of popular interest in gun control. My research on media attention suggests these spikes are extremely short-lived, and that they may be decreasing in intensity.

The wider world is a click away, but whether we mean to or not, we're usually filtering it out.

Increasingly, I'm inspired by entrepreneurs who run nonprofit organizations that fund themselves, or for-profit organizations that achieve social missions while turning a profit.

On Twitter, if you want to quote someone else, you say, RT, re-tweet, that person's name, and then what they said before. And it's a way of essentially saying, I'm not saying this, but my friend said this and I thought this was interesting.

Reddit names are unconnected to real-world identities and it's commonplace for users to create 'throwaway' accounts to reveal sensitive information.

There's no locality on the web - every market is a global market.

It's fine to have social media that connects us with old friends, but we need tools that help us discover new people as well.