Stockholm Tvärbanan - Tram

in the map Tvärbanan (line 30,31) is labeled as “light rail”. But the the Stockholm public transportation company (SL) officially labels the Tvärbanan as “Tram” (see links).
SL recognizes as “light rail” only the Saltsjöbanan (line 25, 26) - normal gauge rails, but not connected to the main railroad network and the Roslangsbanan (line 27, 28, 29) - narrow gauge rail trains, obviously also not connected to main network. Generally speaking, it is probably debatable if the Tvärbanan is actually a tram or a light rail vehicle, since the differences are not well defined, at least as far as I know. Nevertheless the SL officially calles it a tram and all stops have a “Tram” description. From a tourist point of view, this causes cofusion and I think it should be relabeled as a tram line. The other lines called “Tram” by SL are also labelled as tram lines in the map. I want to hear other’s opinions first.

Stockholm public transportation map (PDF) choose “All train services”
(the filename itself contains å, which is not compatible with ASCII of the address line…)

Tvärbanan tram map (PDF)

Off topic, but I can’t resist: When it was built, and the inevitable cost overruns were being debated, some people argued that one reason it got so expensive was that it was built more like a heavy-rail line than a tram…