
Roman Numerals, as used today, are based on seven symbols:
Symbol 	Value
I 	    1
V 	    5
X     	10
L     	50
C     	100
D 	    500
M 	    1,000

Numbers are formed by combining symbols together and adding the values. 
So II is two ones, i.e. 2, and XIII is a ten and three ones, i.e. 13. 
There is no zero in this system, so 207, for example, is CCVII, using the symbols for two hundreds, a five and two ones. 
1066 is MLXVI, one thousand, fifty and ten, a five and a one.

Symbols are placed from left to right in order of value, starting with the largest. 
However, in a few specific cases, to avoid four characters being repeated in succession (such as IIII or XXXX) these can be 
reduced using subtractive notation as follows:

    the numeral I can be placed before V and X to make 4 units (IV) and 9 units (IX respectively)
    X can be placed before L and C to make 40 (XL) and 90 (XC respectively)
    C can be placed before D and M to make 400 (CD) and 900 (CM) according to the same pattern

An example using the above rules would be 1904: this is composed of 1 (one thousand), 9 (nine hundreds), 0 (zero tens), and 4 (four units). 
To write the Roman numeral, each of the non-zero digits should be treated separately. Thus 1,000 = M, 900 = CM, and 4 = IV. Therefore, 1904 is MCMIV.

Below are some examples of the modern use of Roman Numerals.

    1954 as MCMLIV (Trailer for the movie The Last Time I Saw Paris)[6]
    1990 as MCMXC (The title of musical project Enigma's debut album MCMXC a.D., named after the year of its release.)
    2014 as MMXIV - the year of the games of the XXII (22nd, Winter) Olympiad (in Sochi)
