Uber has never reported an annual operating profit, but it will join an elite group of Silicon Valley companies when it lists in New York next month.

Valued at up to $91.5bn, Uber's IPO ranks alongside Amazon in 1997, Google in 2004 and Facebook in 2012 as a vindication for a tech company that has created a new way of looking at the world.

"It's definitely bred a generation of founders that are now inspired to go tackle other physical-world problems that other tech companies hadn't been as open to doing," said Chan Park, a former Uber manager in south-east

On the road: An Uber timeline