To many people, it is still just a dream to use a driverless car. But this dream is now becoming a    1    for people in the American state of Pennsylvania.

The ride-sharing service Uber will start using self-driving cars in a few weeks to carry passengers around the city of Pittsburgh.

Many companies, including Google, Apple and the big U.S. carmakers, are    2    testing driverless vehicles. But this is the first time the American public will    3    get to use them.

The ride service will start out with Ford Fusions    4    with self-driving technology. People using Uber will request the cars through their smartphones. Rides in the self-driving vehicles will be free while the system is    5    in Pittsburgh. Each car will have a driver in front, as a safety measure, to take control of the vehicle if    6    .

Uber also announced a $300 million    7    with an automobile manufacturer, Volvo, to cooperate on self-driving technology and supply vehicles. In the future, Volvo vehicles will be part of the driverless fleet in Pittsburgh.

Kalra, an information scientist with the not-for-profit RAND Corporation, believes driverless cars will be used by car-sharing services in other cities in the coming years. But she said companies like Uber and its main competitor, Lyft, will have to consider several issues before    8    These include laws    9    self-driving technology, population, climate and terrain - the shape and condition of the land.

As for the users, Kalra said they are likely to accept autonomous driving technology very fast. “If the technology is    10    safe, and it behaves in a way that they expect drivers to behave, then I think people will get comfortable very quickly - because it offers so many other benefits.”