Two marriages have been witnessed in the Avatar World, one being of a traditional Fire Nation marriage and one of a Water Tribe marriage.
The arrangement of Roku and Ta Min's wedding was very similar to typical modern day weddings, with specifications such as traditional Fire Nation attire and lavish decor due to the couple's social status. Ta Min mentioned at one point during the reception that separating the husband from the bride was atypical of tradition.
Avatar Kuruk and Ummi's wedding was much more intimate and private, with only a handful of individuals present. Like a traditional Fire Nation wedding, a Water Tribe conjugation featured traditional Water Tribe clothing along with the customary betrothal necklace presented to the bride-to-be. The fact that Kuruk and Ummi's wedding was held at the Spirit Oasis may be an indication that Water Tribe marriages are highly spiritual in nature.