New trains are not built to be coal powered. However there are still some steam trains run and maintained by amateur enthusiasts.
They run on coal :)
Yes
Coal is still used in many steam engines today. Coal is not used on diesel trains or electric trains simply because it is not fuel for them. Electric trains and diesel trains are the most common trains in use, and not trains capable of using coal, because they are more efficent and much less costly to maintain.
Railroad trains have - and continue to - run on any of three powers: Coal (steam), diesel fuel, and electricity.
Only (some) steam engines used coal. It was burnt in a boiler to heat water to steam.
I would think that most trains run on coal but I'm not sure I'll have to check on that. -- Most trains run on diesel fuel these days. In the early days, trains ran on coal or wood to fuel the boilers. Today they have diesel engines that turn generators that power electric motors to drive the wheels. Quite a few trains also run on electricity provided by either a third rail or overhead cables.
What type of coal do they use in trains?
Modern trains are powered by diesel or electricity. There are still some coal powered steam trains in service, mainly on tourist lines.
Steam Trains release steam and coal smoke, because they run on steam generated by heating water with burning coal. Diesel Trains release smoke for the same reasons your car release smoke, it runs on oil.
For warmth, to generate electricity, to run furnaces and steam trains/road tractors etc.
Trains earlier ran on coal. Coal was responsible for ozone depletion.