It depends where you are. Standard Mandarin is your best bet for most places in China and Taiwan, and is about %50 in the US, Canada, etc. Yue Cantonese speakers were the first immigrants to non-Chinese places, but they've pretty much evened out with Mandarin now. In places such as Singapore and Malaysia, where a Chinese language is one of the spoken languages, it's usually also Cantonese. However, the greatest percentage of Chinese speakers are Mandarin speakers.
There are also a couple of less-known dialects in other parts of China.
China has a population of 1.4 billion people, most of whom speak Chinese. That alone makes Chinese the most spoken language. This doesn't even take into account the amount of people that are in Taiwan, Singapore, or other areas where Chinese people live. To whomever posted this, do your homework. "Chinese" isn't a language. The people of China speak many languages but primarily Mandarin and Cantonese. Mandarin is by far the most common as far as I know.
Mandarin Chinese.
China and Singapore would be the only two countries that I know of that have Chinese as an offical language- also people speaking Chinese can be found in most countries.
Roughly 1.2 billion people speak Chinese as their first language, making it the most spoken language in the world.
Chinese language and culture
Mandarin Chinese is the language spoken by the most people in the world as a native language.
English is the most wide-spread language, but as a native language there are more Chinese speakers.
Mandarin Chinese , which is understood by 700 million people
most Chinese people don't know it. I guess only Chinese historians know...
Mandarin Chinese (1,120,000,000 people), then English (480,000,000 people).
Mandarin Chinese is the most spoken language in the world, with over a billion native speakers.
Mandarin Chinese is the language with the most native speakers.