Which of these three languages is the most to least widely spoken, Japanese, Korean, Cantonese Chinese, Mandarin Chinese?

Mandarin Chinese is the most widely spoken language among the options you provided. It is the official language of China, which has the world's largest population. Cantonese Chinese is also a widely spoken language, but it is primarily spoken in the southern region of China, as well as in Hong Kong and Macau. Japanese is spoken in Japan and by some expatriate communities around the world, but its total number of speakers is significantly lower than that of Mandarin and Cantonese. Korean is primarily spoken in Korea, although there are also some Korean-speaking communities in China and other countries. Therefore, the order of the most to least widely spoken languages from the options provided would be Mandarin Chinese, Cantonese Chinese, Korean, and Japanese.

To provide a bit more context, Mandarin Chinese is spoken by over 1 billion people worldwide, making it the most spoken language in the world. It is also the official language of Taiwan and one of the official languages of Singapore. Cantonese Chinese, on the other hand, is spoken by around 60 million people worldwide, with the majority of speakers located in the Guangdong province of China, as well as Hong Kong and Macau. Korean is spoken by around 77 million people worldwide, with the majority of speakers located in North and South Korea. Japanese is spoken by around 130 million people worldwide, primarily in Japan. While all of these languages are important and have significant numbers of speakers, Mandarin Chinese is the most widely spoken of the four.

To provide even more information, Mandarin Chinese is a tonal language, which means that the meaning of a word can change depending on the tone or pitch of the speaker's voice. It uses simplified characters in mainland China and traditional characters in Taiwan and Hong Kong. Cantonese Chinese is also a tonal language, but it has a more complex phonology than Mandarin Chinese, with more distinct vowel and consonant sounds. Korean is unique among the languages in this group in that it has its own writing system called Hangul, which was invented in the 15th century. Japanese uses a combination of Chinese characters (kanji), along with two syllabic scripts called hiragana and katakana. All of these languages have rich cultures and histories associated with them, and learning any of them can be a rewarding and challenging experience.

To expand on the topic further, learning Mandarin Chinese is particularly important for those interested in doing business in China, as it is the most widely spoken language in the country and the official language of government and education. Cantonese Chinese is also important for business and commerce in southern China, Hong Kong, and Macau. Korean is the official language of both North and South Korea, and is also spoken in some parts of China and in Korean communities around the world. Learning Korean is important for anyone interested in Korean culture, entertainment, and technology, as South Korea has a strong presence in these areas. Japanese is spoken mainly in Japan, which has the world's third-largest economy and is a major player in technology, automobiles, and other industries. Learning Japanese can be useful for anyone interested in Japanese culture, history, and technology, as well as for those interested in doing business in Japan. In conclusion, all of these languages have their own unique characteristics and uses, and learning any of them can provide a wealth of opportunities for personal growth, cultural understanding, and professional development.