- In the most primitive form it is on the same level as the track, and there is a fairly large height difference between this 'platform' and the train floor.
- Usually the platform is at an elevated level relative to the track but lower than the train floor.
- Ideally the platform is at the same level as the train floor.
- Occasionally the platform is at a higher level than the train floor. This may be the case when a train with a low floor level serves a station built for trains with a higher floor level, for example at the Dutch stations of the DB Regionalbahn Westfalen (see Enschede). Likewise, on the London Underground some stations are served by both District Line and Piccadilly Line trains, and the Piccadilly trains have lower floors.
Sometimes a tram stop is served by ordinary trams (with rather low floors) as well as metro-like light rail vehicles with higher floors, and the tram stop is provided with a dual height platform (along the track first one height, then an extension with the other height). This applies for example in Amstelveen, Netherlands.
A railway platform provides access to one or two tracks; if it is fork-shaped on one or both ends the number of tracks will be more. Usually not the platforms, but the tracks are numbered. Tracks without platform access, used for through traffic, also have a number. This number may not be indicated, but it shows indirectly by the fact that in the numbering of the accessible platforms a number is skipped.
Some metro stations have screens with doors between the platforms and the tracks. They provide more safety; also they allow the heating or air conditioning on the station and the ventilation in the tunnel to be separated, thus being more efficient and effective. They have been installed in most stations of MTR, Hong Kong, see picture.