W = Broad Gauge
A = AC Electric Traction
M = Mixed (Suitable for both Goods and Passengers)
P = Suitable for only Passenger trains
G = Suitable for Goods trains
C...
more... = DC Electric Traction
CA = Dual Traction (Both AC and DC)
Y = Metre Gauge
Z = Narrow Gauge (2' 6" Gauge)
N = Narrow Gauge (2' Gauge)