There are several places in MusicBrainz that store a set of two dates: "Begin Date" and "End Date"; these have different meanings for different cases. In all cases, the dates can vary in its accuracy from just a year to the exact day, although you cannot enter a day without a month or a month without a year.
The begin and end dates indicate when an artist started and finished its existence. Its exact meaning depends on the type of artist:
- For a person
- Begin date represents date of birth, and end date represents date of death.
- For a group
- Begin date represents the date when the group first formed: if a group dissolved and then reunited, the date is still that of when they first formed. End date represents the date when the group last dissolved: if a group dissolved and then reunited, the date is that of when they last dissolved (if they are together, it should be blank!). For listing other inactivity periods, just use the Annotation and the "member of" relationships.
- For others
- There are no clear indications about how to use dates for artists of the type Other at the moment.
The exact meaning of the begin and end dates depends on the type of label. Note that it's usually hard to know if an imprint has folded or is just on hold, and in generally the end date should only be entered if there's a clear indication of its demise.
- Begin date
- For officially registered trademarks or companies (holdings, distributors), it's the date at which it was registered.
- For imprints, collection names (when used as labels) and subdivisions (or subsidiaries) for which there is no available creation date, it's the release date of the first release ever issued under that label name.
- For bootleg companies (more generally for obscure/dubious companies), it's also tolerable to use the release date of the first release, unless more accurate data is available.
- End date
- For companies (holdings, distributors), it's the date at which the company stopped to exist (be it bankrupted or dismantled).
- For imprints, collection names (when used as labels) and subdivisions (or subsidiaries) for which there is no available dismantling date, it's the release date of the last release ever issued under that label name.
- For bootlegs companies (or otherwise obscure/dubious companies), it's also tolerable to use the release date of the last release, unless one has more accurate information.
The dates indicate when a certain area was founded and/or ceased to exist. For example, the Soviet Union has a begin date of 1922 and an end date of 1991.
The use of dates in relationships depends of the relationship type, and sometimes they are not used at all. Check the page for the specific relationship in the relationship types list to know more.