First and middle names are the names that make up a person's full name. The first name is the name given to a person at birth and is usually the name used to address them in casual and formal settings. The middle name, as the name suggests, comes between the first and last name and is also given at birth. In some cultures, the middle name is considered just as important as the first name, while in others, it is optional or not used at all. Together, the first and middle names form a person's full name and are often used for identification purposes.