In terms of legal recognition, most sovereign states and other jurisdictions limit marriage to opposite-sex couples and a diminishing number of these permit polygyny, child marriages, and forced marriages.Over the twentieth century, a growing number of countries and other jurisdictions have lifted bans on and have established legal recognition for interracial marriage, interfaith marriage, and most recently, gender-neutral marriage.
Conversely, civil marriage does not exist in some countries governed by a religious legal system, such as Saudi Arabia, where marriages contracted abroad might not be recognized if they were contracted contrary to Saudi interpretations of Islamic religious law.
Since the late twentieth century, major social changes in Western countries have led to changes in the demographics of marriage, with the age of first marriage increasing, fewer people marrying, and more couples choosing to cohabit rather than marry.
For example, the number of marriages in Europe decreased by 30% from 1975 to 2005.
In some cultures, marriage is recommended or considered to be compulsory before pursuing any sexual activity.
When defined broadly, marriage is considered a cultural universal. Individuals may marry for several reasons, including legal, social, libidinal, emotional, financial, spiritual, and religious purposes.