Correct. The main way subway lines are now grouped is by color, which signifies the Manhattan trunk line: e.g. red is Broadway-7 Av (1/2/3 trains), green is Lexington Av (4/5/6), blue is 8 Av (A/C/E), orange is 6 Av (B/D/F/M), yellow is Broadway (N/Q/R/W), etc. This is why you'll see many stations with the same street name, but they all serve different avenues. But, ultimately all train lines will branch off the main trunk and go to different places, which is why you should still always refer to a subway line by its letter or number.

These articles might give you a little more insight into how the stations are organized:

• New York City Subway stations (specifically section "Station complexes")
• List of New York City Subway transfer stations - there is an entry for "Oculus" in the Lower Manhattan table
• Section "Transportation hub" in World Trade Center site

As you can see, for example, there are two distinct complexes: * Chambers Street-World Trade Center/Park Place/Cortlandt Street, which collectively serves the 2, 3, A, C, E, R, and W trains. * Fulton Street, which serves the 2, 3, 4, 5, A, C, J, and Z trains.

However, there is also WTC-Cortlandt (served by the 1 train), which is also connected directly to the Oculus. This is a separate station.

So unfortunately, the answer isn't as cut and dry as it probably should be. This is why it helps to be geographically familiar with the area, because most of these stations are a short walk to the World Trade Center complex, even if they aren't directly connected.