Birthday

A birthday is an occasion when a person or institution celebrates the anniversary of their birth. Birthdays are celebrated in numerous cultures, often with a gift, party, or rite of passage.

Many religions celebrate the birth of their founders with special holidays (e.g. Christmas, Buddha's Birthday).

Note the distinction between birthday and birthdate: The former, other than February 29, occurs each year (e.g. May 11), while the latter is the exact date a person was born (e.g., May 11, 1998).

Legal conventions

In most legal systems, one becomes designated as an adult on a particular birthday (usually between 12 and 21), and reaching age-specific milestones confers particular rights and responsibilities. At certain ages, one may become eligible to leave full-time education, or become subject to military conscription or to enlist in the military, to consent to sexual intercourse, to marry, to marry without parental consent, to vote, to run for elected office, to legally purchase (or consume) alcohol and tobacco products, to purchase lottery tickets, or to obtain a driver's licence. The age of majority is the age when minors cease to legally be considered children and assume control over their persons, actions, and decisions, thereby terminating the legal control and legal responsibilities of their parents or guardian over and for them. Most countries set majority between 18 to 21.