In this context, the two factors involved are sometimes spoken of as something you have and something you know. A common example of two-factor authentication is a bank card: the card itself is the physical item and the personal identification number (PIN) is the data that goes with it.
The 49ers would become the second best team in the league until it dissolved after the 49ers first season, and they joined the NFL ranks along with the Cleveland Browns and the Baltimore Colts. The San Francisco 49ers get their name from the California gold-seekers who stampeded the area in 1849.
In the case of the Giants the New York Football Giants is their corporation name. Moreover as part of the deal which would move the Giants to New Jersey, Wellington Mara negotiated an agreement with New Jersey governor William Cahill that they would still be called the New York Giants after the move.