In Portuguese temos apenas one word que descreve ‘object that transports materiais or people através de um carpet com rolos.’ But in English there are four different names!
TREADMILL
Good for walking and running.
CONVEYOR BELT
It transports materials and objects.
CAROUSEL
It transports bags, especially in airports. Some people call it Conveyor Belt, too.
MOVING WALKWAY
It transports people, especially in airports.

IMAGE COURTESY:
• http://i.ebayimg.com/00/s/NTY2WDg0OQ==/z/ZywAAOSwd4tTs660/$_32.JPG?set_id=880000500F
• http://www.trbimg.com/img-55ff30ce/turbine/ct-ohare-united-moving-walkway-getting-around-met-0921-20150920
• http://axgig.com/images/86095611577901261799.jpg
IMAGE COURTESY: IMAGENS INTERNAS AO POST:
• treadmill: https://images-na.ssl-images-amazon.com/images/I/814YUsshaFL._SL1500_.jpg
• conveyor belt: http://images.wisegeek.com/bottles-on-assembly-line.jpg
•carousel: http://img.directindustry.com/images_di/photo-g/5796-9023140.jpg
•moving walkway: http://img.archiexpo.com/images_ae/photo-g/3425-1515065.jpg