I am not sure if there is such a big difference between the different types of track (usage): In particular, for "sidingTrack" and "connectingTrack" the usage is the same like the possible usage. Major physical characteristics of the track are - so far - not modelled in railML.

• Wiki, attributes: This is a regular track a of line used for frequent passenger and freight transport.
  
• Wiki, best practice: NO: hovedtogspor/hovedspor, DE: Durchgehendes Hauptgleis, de-CH: Hauptgleis/Signalisiertes Gleis, fr-CH: Voie signalée, it-CH: Binario segnalato, NL: Hoofdspoorweg, CZ: Hlavní kolej
  
• Forum: Main tracks of the line and their continuation in the station.
  

• Wiki, attributes: This is a track not frequently used (e. g. loops for overtaking and/or crossing in stations).
  
• Wiki, best practice: NO: togspor, DE: nicht-durchgehendes Hauptgleis, NL: Lokaalspoorweg, CZ: Spojovací kolej
  
• Forum: Other signalised tracks (with train routes).
  

• Wiki, attributes: This is a siding.
  
• Wiki, best practice: NO: øvrige spor/sidespor, DE: Nebengleis, de-CH: Nebengleis/Nicht-signalisiertes Gleis, fr-CH: Voie non-signalée, it-CH: Binario non segnalato, NL: Raccordement, CZ: Manipulační koleje
  
• Forum: Non-signalised tracks (without train routes, but possibly shunting rountes)