The sharing economy can encompass a lot. There's tool sharing — whether that's bike-sharing, car-sharing or actual sharing-sharing. It also includes a subset called the peer economy, which describes peer-to-peer platforms in which people sell things to one another. There's also a subset called the "gift economy," which is stuff like couch-surfing through platforms like Airbnb. Speaking of which, the Airbnb co-founder Joe Gebbia described this movement this way, : "Social media is about sharing online. We've extended that behavior into the offline world. In the wake of the recession, there's a slightly different mentality beginning to emerge, which is that access is more powerful than ownership. The last century was predicated around ownership as status. There's an opportunity for this century to be defined by access as status. You see this across all industries. Zipcar is a great example. You don't need to own a car; having access to Zipcar actually gets you status. Suddenly, you can be the guy with the car when it's needed. For Airbnb, you don't need a vacation home anymore. You have access to 500,000 of them when you want them."