New York Department Of Vital Statistics Birth Certificate
It is better to have a birth certificate copy, because this copy can be more easily replaced in the event of a loss. If for some reason a child needs their certificate to enroll in some type of youth sports, it is easier to breathe knowing that a copy is more easily obtained than an irreplaceable original.
There's a plethora of reasons to have a birth record on hand. School children cannot be enrolled without one. Enlisting into the army cannot be done without proper identification. Opening a bank account, obtaining a passport or visa card, getting a credit card at your bank, receiving an inheritance, and even being married can all be hampered without a birth record.