When you hear “sharing economy,” what immediately comes to mind? For me, it’s a mix of fear and excitement. I remember the day when I was afraid to get in an Uber because my parents taught me not to get in a car with strangers. I remember at a later date how excited I was to plan a more affordable vacation because I arranged lodging in someone else's home through AirBnB. I've gradually become comfortable with—and happy about—this new economy. But where did it come from and where is it going?