| IDateTimeProvider | The interface for providing DateTime information |
| IExtendedDateTimeCollectionChild | The extended date time collection child interface |
| IExtendedDateTimeExtremityProvider | The extended date time extremity provider, provides methods to get the earliest and latest possible date times |
| IExtendedDateTimeIndependentType | The extended date time independent type interface |
| IHolidayProvider | An interface to provide access to holiday information |
| ISingleExtendedDateTimeType | The single extended date time type. |
| RangeDirection | The range direction enum, indicates in which direction to move the ranges values |