This package contains an implentation base class for all identifier helper classes - AtlasDetectorID. This class contains the information of the "upper levels" of identifiers, i.e. which detector system (InDet, LAr, Tile, Muon) and which subdetector. All concrete helpers derive from AtlasDetectorID and thus each one can respond to the generic queries on the upper levels of identifiers.

AtlasDetectorID also provides facilities for printing out identifiers, e.g. show_to_string, and maintains the version tags.