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.

Bob Moore, historian for the Kansas City Chiefs told the Associated Press in 2012, “the Roman numerals made it much more important.” After all, the fledgling game at the time was the ...

Some elements, particularly the transition metals, do not always have the same valency in their different compounds. The valency of these elements is usually given in roman numerals inside brackets.