Unlike many other ancient systems, Roman numerals are still in use today ... of writing numbers that uses combinations of ...

Roman numerals are a numeral system which was used in Ancient Rome. It uses letters instead of numbers to represent values. You may have seen Roman numerals on clocks and on TV or film credits.

That's Super Bowl 59 for those untrained in Roman numerals, featuring the Kansas ... which means one less than 50. New letters wouldn't be introduced until Super Bowl 100, which would be C.