Why the preference for digits over letters? It mostly has to do with ease of memorization. To a native English-speaker, remembering a long string of digits might seem harder than memorizing a word. But that’s if you understand the word. For many Chinese, numbers are easier to remember than Latin characters. Sure, Chinese children learn the pinyin system that uses the Roman alphabet to spell out Mandarin words (for example, the word for “Internet,” 网络, is spelled wangluo in pinyin). And yes, Arabic numerals (1-2-3) are technically just as much a foreign import as the Roman alphabet (A-B-C). But most Chinese are more familiar with numbers than letters, especially those who didn’t go to college. To many, “Hotmail.com” might as well be Cyrillic.