(1) People with spare bedrooms would welcome strangers into their homes and share restaurant recommendations with them for a small fee.

(2) Fast forward to 2016 and the big, successful Airbnb is considered a mainstay of what we now call "the sharing economy".

(3) Back in 2008 a small company in San Francisco called Airbnb had a dream.

(4) It is also the business that defines the mentality of the millennial.