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.
1 From mid 19th century: sourdough bread (named after the Gold Rush prospectors who guarded sourdough starter in their pockets; the SF 49ers mascot is also 'Sourdough Sam')  Late 19th century: cioppino (from Portuguese and Italian fishermen who settled in North Beach; happens to go well with sourdough...)