Mandarin is by far the most widely spoken. Others don't even come close. Cantonese is the other one that people consider common, but... http://www.wolframalpha.

Mandarin is by far the most widely spoken. Others don't even come close. Cantonese is the other one that people consider common, but... http://www.wolframalpha.com/input/?i=mandarin+%7C+cantonese http://www.wolframalpha.com/input/?i=mandarin+%7C+cantonese