Roman Numerals

First off what are Roman Numerals and why are they still relevant?
  Roman Numerals were the symbols that utilized letters from the Roman alphabet, collectively known as an ancient numerical system used in Ancient Rome. Today we use Roman Numerals for copyright credits at the end of films, organization of outlines (i) (ii) (iii) (iv), numbering Super Bowls, names of Monarchs and royalty.

What are our Roman Numerals?
  I=1
  V=5
  X=10
  L=50
  C=100
  D=500
  M=1,000
 

 The following were introduced later to represent larger, more complex numbers. They should be represented with a Bar over their tops. These however are highly unlikely to be on any Number Sense tests.

*V=5,000
*X=10,000
*L=50,000
*C=100,000
*D=500,000
*M=1,000,000