What Is Roman Numerals?
Roman numerals represent numbers using combinations of seven letters: I (1), V (5), X (10), L (50), C (100), D (500), and M (1000). Letters are generally added together left to right, except when a smaller value appears before a larger one, which means subtract instead — like IV meaning 4 (5 − 1), not 6.
Example
1994 is written in Roman numerals as MCMXCIV: M (1000) + CM (900) + XC (90) + IV (4) = 1994.