Two different forms of numerals exist in Arabic text. You can write precisely the same number using either of the two systems of numerals. This means you can use either Arabic numerals or Hindi numerals to write numbers in Arabic typesetting. But what’s the difference and which is best to use?
What are Arabic numerals and Hindi numerals?
Arabic numerals (or “Western Arabic”) are numbers written in the same form as they would be in English. “Hindi numerals” (or “Eastern Arabic”) work the same but look different, as this chart shows:
Arabic typesetting uses either “Arabic numerals” or “Hindi numerals”
Although Arabic text is written from right to left, numbers are always read from left to right – whichever form of numerals are used.
What about “Roman numerals”?
Roman numerals are a quite different system of writing numbers, using letters for particular amounts. TV programmes made by the BBC have their year of production written in Roman numerals at the end of the credits. For instance, “2011” is “MMXI” and “1984” is “MCMLXXXIV”. These are never used in Arabic typesetting.
Which are best?
Either Hindi or Arabic numerals can be used but which is most appropriate depends on factors such as the purpose of the document, the type and location of the audience, etc.
Arabic typesetting for Algeria or Morocco should definitely lean towards using Arabic numerals (remember how they are also called “Western Arabic numerals”). Arabic typesetting for, say, Saudi Arabia or UAE should lean towards using Hindi numerals. However, some “house styles” in the Middle East call for Arabic numerals. Another factor to consider is Arabic numerals are more suited to a multilingual audience, as these have become the de facto globalised standard. If you are unsure which numerals to use for your Arabic audience, it might be best to seek expert advice, ask the end client or be prepared to change on proof.
Choosing Arabic or Hindi numerals in InDesign
Switching between Arabic and Hindi numerals is extremely easy in InDesign ME. Select the text to be changed, go to the Digits menu in the Character Palette and choose “Arabic” or “Hindi”. The various plug-ins that allow access to the World Ready Composer have similar, simple to use menu options. That is, of course, assuming that the font you are using supports both.
If you have a font that contains Hindi numerals, you can even “type” them using the Glyph palette in the English version of InDesign. They are in the Unicode table at 0660 to 0669 (PDF of Unicode 6.0 chart for Arabic). On the Mac, you can even change your keyboard to Arabic (enable it in System Preference’s Language & Text) and then just type numbers in an Arabic font to get Hindi numerals. Be a little careful though: as you are actually typing the Hindi numerals directly, these will not change back to Arabic numerals if you change your settings or font. Be aware too that entering Arabic words this way in English InDesign “out of the box” will not compose the letters correctly.
You can also switch how numbers are displayed in Word in Advanced Word Options.
Can I mix and match?
On the whole, you pick either Arabic numerals or Hindi numerals and stick to that system within a given publication. The only exception would be in pieces of “foreign” text within the Arabic typesetting. For instance, in a document using Hindi numerals, it might well make sense to leave an English postcode or the number of an ISO standard in Arabic numerals.
That’s an overview of Arabic and Hindi numerals. If you want to know more, feel free to ask. For a more general overview, read my earlier post on Arabic typesetting.