Human is born lazy and selfish. A quote that everybody knows. Additional to the way we want to be smarter, act clever, and move faster did the concept of the well-known taxis invent.
It helped us form a link between A and B especially for the busy people without cars living in the cities.
The taxis include educated drivers, recognizable cars with taxi medallions, and clear restrictions but well-paid rides.
This actual concept did Travis Kalanick reorganize in his way. He made the whole concept with taxi services and with a professional setup, to a price that is way too cheaper than a usual taxi ride.
He named it "Uber". Uber is made through an online setup in both ways of paying and booking, which makes it easier for the driver and the customer. 
Uber was launched back in 2012, and now there are Uber cars available in more than 700 cities around the world.