The term “marriage”, in the context of the family tree, is entirely a matter for the user. It is intended to show a relationship that is normally a marriage in the eyes of the law. However, you can use this to show any formal or informal arrangement. Indeed, you can even have same-sex marriages recorded here. There is no limit to the number of marriages. You can either create a new person here or link to a person already in the data.
Created with the Personal Edition of HelpNDoc: What is a Help Authoring tool?