Some people write 4 with an open top while others write it with a pointy triangular top. Some people write 3 with a flat top, others with a curvy top. Many Europeans write 1 with a long "hat" (looking a lot like an American 7) while Americans tend to write it either as a single straight line, or with a short "hat" and a base. Many computer geeks and engineers often cross their 0's to distinguish them from the letter O, but this doesn't work for Danish-speakers, for whom Ø is a different letter. Third, the numerals are written differently in different parts of the world, when written by hand: Spelling exception is number 9, which spelling change from neuf to neuvième. We call our numerals "Arabic" (or "Hindu-Arabic" if we're being more accurate) but they are not the same as the classical Arabic or Hindu numerals. To form ordinal numbers in French the ending - ième is added to the cardinal number (6, 7, 8, etc.), but pay attention that cardinal numbers that end in - e, drop e before adding the ending -ième to avoid pronunciation difficulties, ex. So there was a huge advantage to people in switching from other numeral systems to the modern one, back in the day when most calculation was done by hand. Go look up the Greek-Hebrew one it's great for making secret codes but lousy for doing long division.
And most other number systems were worse than Roman numerals. Doing it in Roman numerals is a lot harder: DLXXIV × IX: first you have to unpack the subtractives IV and IX to form IIII and VIIII then you multiply each digit on the left by each on the right then you sort them in descending order and then you group up any IIIII's to make V's and so on. In every language forms connected with counting include several grammar types: the declension of nouns and other nominal parts of speech in number. If you want to multiply 574 × 9, you can multiply 500 × 9, 70 × 9, and 4 × 9 and then add up the results. Most typesetting will not have to get involved in the details of this, but it’s interesting stuff. The Finish for one is yksi while eleven is yksitoista one repeated. For instance, the French for 81 translates literally as Four twenties and one. These fantastic posters featuring the numbers 1-10 in 10 different languages are a great resource to help you promote and celebrate the European Day of Languages. If two programming languages use exact same function, theoretically they should give same random number. The big difference is in place value, which means you can calculate one digit at a time and add up the results quickly. Of course, numbers that are writen out in words can reveal interesting patterns too. For example, Java uses Linear Congruential generator. First, not all numeral systems are created equal! It is actually a lot easier to do arithmetic with Hindu-Arabic numerals (the ones we use) than with Roman numerals, Mayan numerals, Greek-Hebrew numerals, or Babylonian numerals.