MONOGAMY: happens when both married partners only have one spouse
POLYGAMY: occurs when one individual has multiple spouses.
POLYGYNY: happens when one man is married to more than one woman simultaneously.
POLYANDRY: refers to the condition when a woman is married to more than one man simultaneously.
ENDOGAMY: the custom of marrying only within the limits of a local community, clan, or tribe.
EXOGAMY: the custom of marrying outside a community, clan, or tribe.