Roman numerals converted from 1 to 1,000

Until the late-medieval period, Roman numerals were the most common way of displaying numerical data in Europe. It was only when (primarily Italian) traders and scholars, such as the mathematician Fibonacci, returned from their travels in Asia and North Africa that our current system of Arabic numerals became more popular in Europe. The main reason being their easier usage for calculations, including decimalization.

No Zero

Another major difference between Arabic and Roman numerals is the ability to represent nothing. Arabic numerals include the number 0 (zero), whereas there was no Roman equivalent to this. In the middle ages and earlier, zero was written as the word "nulla". Early mathematicians, such as Aristotle, also dismissed the idea of having a numerical zero, as it could not be used to multiply or divide. When Arab mathematicians tried to introduce the concept of zero to Europe in the eighth century, it was met with resistance, and in later centuries the use of zero and other Arabic numerals was made illegal for European bankers, as this was seen as a foreign challenge to the traditional system of numbers.

Extremely long numbers

One further advantage of the Arabic system is that numbers are much shorter when they get to higher values. For example, the number 3,888 is written as "MMMDCCCLXXXVIII " in Roman numerals, which is fifteen individual numerals. In order to prevent the numbers from becoming too long, Roman mathematicians opted to draw a line above the base integers (V, X, L, etc.) to show that the number had been multiplied by one thousand, starting at 4,000. This means that the number 4,000 is written as 'IV' with a short line above it, 4,001 would be written as 'IVI' with a horizontal line above the 'IV' only, and not the second 'I', and so on.