Subway lines are designated as express or local, so for the most part once you know if a line (like the number 2 train) is express, it is always called the express (so there's not a 2 local versus

3. The difference between express and local NYC trains. Every single New Yorker has a story about a local train going express, or getting on the wrong train at some point in their life. You'll feel foolish but it's a rite of passage. Each different train line (represented by colors) has its own local and express trains.

For example, in a subway system, a bottleneck occurs when the train capacity cannot satisfy the passenger transport demand, whereas in vehicular traffic systems, a bottleneck refers to vehicular congestion. (3) The train flow patterns in a subway system are significantly different from the bus flow patterns in a traditional public transit networks.
Commuter rail runs on a fixed schedule, most frequently at commuter rush hours and to some very non touristy place where people live and commute to work in the city. The price of rides vary, depending on distance. A commuter rail ride to Salem is $7.50. All subway rides are $2.75. Do not be intimidated by the inbound/outbound stuff of the subway.
Chicago’s main train system is colloquially referred to as “the L.”. It consists of eight train lines—Red, Blue, Green, Brown, Orange, Pink, Purple, and Yellow. “L” is derived from “El” which is in turn an abbreviation for “elevated” which refers to the fact that much of the system is on elevated tracks that run above
Beware, some trains only run at certain times. While the NYC subway system runs 24 hours, generally the Express trains stop running around 10:30pm. All the local trains will still keep running. Their routes, however, may change. This is an example of a train line that changes at night. This is indicating that at night, the 4 train stops on the ZI0x. 676 819 414 614 987 703 646 862

difference between train and subway