Zero is the only number that cannot be represented by Roman numerals. The word nulla (Latin for “none”) was used by medieval computists in lieu of 0.
The Roman Numerals System is an old numeric system developed by the Romans and used by most Europeans from the 7th – the 6th century BC and almost until the late Middle Ages. There are seven symbols in this system: I, V, X, L, C, D, M (1, 5, 10, 50, 100, 500, 1000).
Around the 12th century, Hindu-Arabic numerals (also known as Arabic numerals) were introduced to Europe and now it is the most common numeric system in the world today. However Roman numerals are still used especially in pharmacy, chemistry, photography, seismology, etc.
On the other hand, the Romans didn’t have a symbol for the number zero (0). Because Roman Numerals System was developed for mostly knowing the price of goods, and to trade. So, there was no need for a symbol to represent zero.
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