Definition:Roman Numerals

Definition
The Roman numerals are:

To express other numbers than these, symbols are placed next to each other so as to cumulate: for example:
 * $\text {II}$ means $2$
 * $\text {CCXVI}$ means $216$.

For brevity in presentation, the technique is used of placing a smaller denomination in front of a larger one so as to subtract the former from the latter

For example:
 * $\text {IV}$ means $4$
 * $\text {XCIX}$ means $99$ (although $\text {IC}$ could be used, it is not).