Most genealogy software gives you one field for the date of marriage, and one field for the place of marriage.
However, there are some complex unions that do not take place on just one day and one place. In genealogical data, I've seen up to 4 components of a marriage:
The Legal Marriage: When the couple signs the wedding document with witnesses.
The Wedding Ceremony: When the couple are non-legally declared to be married.
The Religious Marriage: When the couple signs the offical document declaring them married according to their religion in front of witnesses.
The Religious Ceremony: When the couple are declared to be married according to their religion.
These four events usually occur on the same date and in the same place. But that need not be the case, and each can occur on different dates in different cities.
How should this be recorded in genealogy software, and what (if any) of these events should take precedence as the "Marriage" event if the software only allows one event?