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A maglev train floats about 10 mm above the guideway on at magnetic field and is propelled by a linear induction motor.They follow guidance tracks with magnets.Once the train is pulled into the next section，the magnetism switches so that the train is pulled on again.Because of the lack of physical contact between the track and the vehicle，the only friction is that between the carriages and the air.As a result，maglev trains can potentially travel at very high speeds with reasonable energy consumption and noise levels.These trains are often referred to as Magnetically Levitated trains which are abbreviated to Maglev.Though maglevs don't use steel wheel on steel rail，the dictionary definition of a train is a long line of vehicles travelling in the same direction—it is a train.Maglev train use electromagnetic technology to allow trains to actually hover above the ground.With the friction of wheels on rails gone，a whole new era of high speed trains is possible.

The world's first commercial automated system was a low-speed maglev shuttle that ran from the airport terminal of Birmingham International Airport（UK）to the nearby Birmingham International Railway Station from 1984 to 1995.The length of me track was 600 m，and trains“flew”at an altitude of 15 mm.It became effective for nearly eleven years，but the out-of-date electronic systems made it unreliable in its later years and it has now been replaced with a cable-drawn system.

Transrapid，a German maglev company with a test track in Emsland，constructed the first operational high-speed conventional maglev railway in the world，the Shanghai Maglev Train from Shanghai Railway Station to new Shanghai airport at Pudong.It was inaugurated in 2002.