Monogamy is a form of marriage in which each married partner is allowed to have only one spouse at any given time. This is the most common form of marriage in many parts of the world today, particularly in Western industrialised societies, and is often legally recognised as the only legitimate form of marriage. Monogamy can be contrasted with polygamy, which involves having more than one spouse at the same time (either polygyny, where a man has multiple wives, or polyandry, where a woman has multiple husbands). Serial monogamy, where individuals have multiple spouses throughout their lives but only one at a time, is also a common pattern in some societies. The prevalence and social norms surrounding monogamy vary across cultures and are influenced by factors such as religion, law, and economic conditions.