Abandoned & disused differences for railways?

Hi

What’s the difference between abandoned & disused?

This page:

http://wiki.openstreetmap.org/wiki/Proposed_features/Railway

includes both, but no clarification of their differences.

Cheers
Dave F.

abandoned: The course of a former railway which has been abandoned and the track and infrastucture removed.
disused: A section of railway which is no longer used but where the track and infrastructure remains in place. See disused=yes for alternative tagging.

from: http://wiki.openstreetmap.org/wiki/Map_Features#Railway