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.
The word "marriage" derives from Middle English mariage, which first appears in 1250–1300 CE.
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.
Some cultures allow the dissolution of marriage through divorce or annulment.
In some areas, child marriages and polygamy may occur in spite of national laws against the practice.