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

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Many cultures have one or more coming of age birthdays:
• In Canada and the United States, families often mark a girl's 16th birthday with a "sweet sixteen" celebration – often represented in popular culture.
• In some Hispanic countries, as well

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In many parts of the world, an individual's birthday is celebrated by a party where a specially made cake, usually decorated with lettering and the person's age, is presented. The cake is traditionally studded with the same number of lit candles as the age of the

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In the Gregorian calendar (a common solar calendar), February in a leap year has 29 days instead of the usual 28, so the year lasts 366 days instead of the usual 365.
A person born on February 29 may be called a "leapling" or a "leaper". In common years, they usually

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Buddhism (Mahayana)
Many monasteries celebrate the anniversary of Buddha's birth, usually in a highly formal, ritualized manner. They treat Buddha's statue as if it was Buddha himself, as if he were alive; bathing, and "feeding" him.

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Ancient Persia
According to Herodotus (5th century BC), of all the days in the year, the one which the Persianscelebrate most is their birthday. It was customary to have the board furnished on that day with an ampler supply than common: the

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Birthdays are fairly evenly distributed through the year, with some seasonal effects.
In the United States, there tend to be more births in September and October. This may be because there is a holiday season nine months before (the human

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