What are Cantonese and Mandarin?
Mandarin and Cantonese are both tonal languages (different tones indicate different words in the same way that pronunciation does). They both belong to the Chinese branch of the Sino-Tibetan language family. They are two clearly differentiated Chinese languages. They are separate sub-branches of Chinese, not merely dialects or local varieties, and they are largely mutually unintelligible.
Mandarin is the majority Chinese language in China (spoken by about 70% of the population). Cantonese is one of about six less-spoken Chinese languages with the same roots in ancient Chinese, including Wu (Shanghainese) and Min (Fujianese), which also each have about 6% of China’s population using them as a first language.
To learn Cantonese or Mandarin definitely depends on your personal choice and your reasons for learning, e.g. which people you want to interact with.
Local people in certain areas tend to learn Cantonese naturally through exposure to their parents, whereas Mandarin is generally taught in schools, and only learned at home at an early age when there is no other local language in use.
2. Which is easier Cantonese or Mandarin?
Without a unified romanization system, you may find a lack of learning resources for Cantonese. While, Mandarin, is studied China-wide, including in schools in Hong Kong, as well as more broadly internationally.
In terms of punctuation, Cantonese has more finals and tones which make it harder to learn, not to mention using traditional characters, which are about twice as complicated as simplified Chinese characters generally used for Mandarin.
3. Can Cantonese understand Mandarin?
Although spoken Mandarin and Cantonese are not mutually intelligible phonetically and have differences in grammar and vocabulary, someone who speaks Mandarin will have many clues and a similar language framework to use to begin understanding Cantonese and vice versa.
They share written forms, though simplified/traditional character conversion is needed, which makes the reading of the two languages similar and generally mutually understandable.
Mandarin and Cantonese are spoken in China and in overseas Chinese populations and communities, and where you go will dictate which one you will encounter.
Mandarin is the lingua franca of China and the official language of China (you can learn some basics here). It is the main Chinese language used throughout the big cities, but many cities and provinces have also retained their local languages and dialects. Mandarin and its local dialects prevail in most of northern and central China, including Beijing.