What they mean is that you have many different train operators who run different portions on the track as independent lines, but seamlessly, without connections, your train will become another line’s train when you reach the border stations.

For example, let’s say you are going from Motomachi Chukagai to Kawagoe, try plugging this into Google Maps - you board the Minatomirai line, then once you reach Yokohama, without getting off your seat you are now on the Tokyu Toyoko line, then again at Shibuya it becomes the Tokyo Metro Fukutoshin line, then again at Wakoshi it becomes the Tobu Tojo line.

4 different train operators maintained and run by 4 different companies with their own rolling stock and drivers, but they share access to the track and trains, they interoperate, and it just feels like one train with no dip in service quality. Many lines here do this.

That is not what they wrote, but what you describe sure sounds like an interesting design that I don't recall in countries other than Japan.

The difference is in the mode of service. “Trains”/“railways” run less-frequent service over longer distances, with stations often spaced further apart and certain runs that may skip stations. You typically schedule your trip based on the train’s schedule. “Subway”/“metro” service is typically frequent enough that you can just show up and ride. Outside of Tokyo, the seating arrangements are usually different, with “trains” employing transverse seating and “subways” using longitudinal seating.

My comment said:

> > What's kinda interesting is does that train classify as metro transit that goes slightly beyond city to airport and such (making many stops all the way) or distance intercity train that happens to stop both at airport and city? Or does it change this classification? That would be actually unusual

Also, about this part:

> You typically schedule your trip based on the train’s schedule.

Many counterexamples to that around East Asia (and probably Europe?). Trains are frequent enough that you just come most of the day. Apart from late hours when it is the same for both metro and distance trains, you have to know when they depart because both become rare and you can be late for the last one.

I’m speaking specifically about my lived experience using through-running services in Tokyo. Since your questions in this thread reveal that you lack familiarity with this service plan, I encourage you to visit Japan sometime and experience it yourself.

Turns out, I am intimately familiar with this service plan. There are metro trains with more frequent stops and service and there are distance trains with rarer stops (and yes, rarer service, the degree of which varies by country). What is new that I am missing?

Do you defend the subway vs. train terminology? Sometimes distance trains run underground, sometimes metro trains run overground, so it seems pretty pointless to me.

Most subways have move above ground sections than underground. That is why the article uses the term "metro" not subway - it better describes something useful about the system. A Metro is a system that runs completely separate from other traffic - this forces bridges or tunnels where other traffic needs to cross it.

Yes. Subway train that goes over ground is just train. Metro or long distance is an actual distinction. If they blend in Japan then that's rare.

Typically trains are powered from above, and subways are powered from the rails. Perhaps this is the distinction, rather than running underground.

Really depends on the region and any pre-existing constraints at the time of electrification. A better distinction is probably rapid transit (metro, subway, the Tube, MTR/MRT) vs commuter rail.

Apparently in the US there are trains that use dual rail and overhead power, one for subway and another for overground portions.

I suppose a subway train with rail only supply that goes overground sometimes is more dangerous because it is easier to accidentally step on a rail and rail is powered?

This is common in London as the suburban rail network there is a mix of third rail and overhead lines.

Not in Tokyo. All but the first two of Tokyo’s subway lines run on overhead wires. In fact they had to build most of the subway lines to suburban rail standards because they planned on operating through services in the beginning.

Typically, trains power themselves.

Also not really true. There are trains all over the world that draw power from over head lines and from 3rd and 4th rail systems.

I design rail systems. That is not true, except maybe in your city.