# Roman numerals

A numeral system originating in ancient Rome. Throughout the centuries, there has been variation in some of its symbols - specification, the substractive notation (which uses, e.g. IV to denote 4 instead of IIII) has only entered universal use in modern times. For example, Forme of Cury, a manuscript from 1390, uses IX for 9, but IIII for 4. Another document in the same manuscript, from 1381, uses IV and IX. A third document in the same manuscript uses IIII, IV, and IX.

Some rules regarding Roman numerals state that a symbol representing 10^x may not precede any symbol larger than 10^(x + 1); use XCIX not IC for 99.

The "modern" Roman numerals, post-Victorian era, are shown below:

RomanArabicNotes
I1
II2
III3
IV 4IIII is still used on clock faces
V 5
VI6
VII7
VIII8
IX9
X10
XI11
XIV 14
XV 15
XIX19
XX20
XXX30
XL40
L50
LX60
XC90
C100This is the origin of using the slang term "C-bill" for "\$100 bill".
CC200
CD400
D500
CM900
M1000
1000conjoined C and D, alternative to M
MCMXLV1945
MIM1999Note: this may not be correct, as some claim that 'I' can only precede 'V' or 'X'.
The rumor that Nintendo would release a sequel to the Mario Is Missing game in the year 1999 turned out to be false.
MCMXCIX1999More "correct"
5000
10000
Reversed 100Used in combination with C and I to form large numbers