I know that shorter messages are better in terms of reply rate. The optimal length is something like 50 characters. Characters, not words.

You take a picture of yourself in some exceptional situation - skydiving or whatever. People always post those photos because it works - you're saying something about yourself that begs a conversation and that's what the users are there for.

A great piece of advice for online dating is to stand out from the crowd. So greetings like "hello" and "hi" are very common. They do less well than things that are a little bit quirky or a little bit weird, like "howdy" or "holla." The rarer your salutation, the better it does, in general.

Even at the person-to-person level, to be universally liked is to be relatively ignored. To be disliked by some is to be loved all the more by others. And, specifically, a woman’s overall sex appeal is enhanced when some men find her ugly.

Twitter, Reddit, Tumblr, Instagram, all these companies are businesses first, but, as a close second, they're demographers of unprecedented reach, thoroughness, and importance. Practically as an accident, digital data can now show us how we fight, how we love, how we age, who we are, and how we're changing. All we have to do is look.

There will be more words written on Twitter in the next two years than contained in all books ever printed.

We noticed recently that people didn't like it when Facebook "experimented" with their news feed. Even the FTC is getting involved. But guess what, everybody: if you use the Internet, you're the subject of hundreds of experiments at any given time, on every site. That's how websites work.