Margaret Thatcher née Roberts? Hillary Diane Rodham Clinton? Catherine Zeta-Jones? What do all these surname distinctions mean?

Surname customs vary from culture to culture. In some traditions, a woman adopts her husband's surname when she is married; in other cultures, a woman retains her family name throughout her lifetime. As a result of second-wave feminism, new surname conventions have evolved over the last fifty years, including the institution of hyphenated last names.

In the English-speaking world, surnames are passed down patrilineally and married women adopt their husbands' surnames. This is the case in the United States, the United Kingdom, Australia, New Zealand, and much of Canada. The exception to this is Scotland, where women have only recently begun to take their husbands' surnames (before that, the Scottish tradition was for women to retain their family names).

The borrowed-from-French word "née," pronounced nay, is used to refer to a woman's maiden name. In France and French Canada, the norm is for women to keep their family name as their legal surname-used on official identification and legal documents-but to use their married name in professional and everyday life.

In Germany, a married couple can choose to retain their own surnames, adopt one another's, or combine them, but in any case they must declare an official "family name" that will be passed down to their children.

The American convention is for women to adopt their husbands' surnames. About 25% use their maiden name as a middle name after they are married. But some women will choose not to adopt their husbands' surnames at all. If a woman has already achieved fame and recognition in her career as an actress or a novelist, for instance, she may choose to keep the name by which she is widely known. Others, like Hilary Rodham Clinton, use both surnames. Very, very rare is the practice of a man adopting his wife's surname. Only seven states in the U.S. allow for a man to change his surname upon marriage; in the rest of the 43 states, it would require a court-order name change for a man to do so.

In the field of genealogy, all women are known by their maiden names. This means that whatever surname a woman chose to go by during her lifetime, in genealogical records she will be known by the name she was given at birth.