The most distinct difference between these dialects is in their phonetics, followed by vocabulary differences. Only minor variations in dialects can be seen in their grammatical structures.
Just like each country in Europe has its own language which has unique phonetic and pronunciation rules, so do the dialects of Chinese. Let’s look at Wu and Mandarin as an example. Chinese syllables consist of three elements: initial sound生母(shēng mǔ), final sound韵母(yùn mǔ) and tone语调(yǔ diào). The Wu dialect has three types of plosives: voiced [b, d, g], voiceless unaspirated [p, t, k] and voiceless aspirated [p ', t', k '] while Mandarin and Cantonese do not have voiced consonants. This can render certain Wu words unrecognizable for Mandarin speakers. In contrast, when it comes to the final sound, Mandarin has 13 compound finals while most of other dialects have far less. Sounds using compound finals like ai, ei, ao, ou in Mandarin are often pronounced using single finals in other dialects. For example, “开“ /kāi/ (verb, meaning open) in Wu is pronounced as /kē/.
Regarding the tones, Mandarin only has five main tones: dark level, light level, rising, departing and neutral; Yue Dialect, on the other hand, has nine tone types: dark flat, dark rising, dark departing, light flat, light rising, light departing, upper dark entering, lower dark entering, and light entering. The line between certain tones can be very subtle; emphasis on the wrong syllables may cause difficulties in communication and maybe even misunderstanding. In terms of difference in vocabulary, here are some examples. In a Beijing restaurant, you can order “馄饨“／hún tún／which is called 抄手/chāo shǒu/ in Sichuan or 扁食/biǎn shí / in Min region. You can refer to your father in Wu dialect as “阿爹“ /ā diē / but in Yue dialect father is often addressed as 老竇lǎo dǒu.
The main difference in grammar between different dialects lies in the word order. For example, the sentence “Give this book back to you”. Mandarin: 把书还你(“ to give the book back to you”) Xiang: 书把还你 (“ book to give back to you”) Another well known example is the sentence: "I leave first". Mandarin: 我先走 ("I first leave") Cantonese: 我走先 ("I leave first") These differences in phonetics, vocabulary and word order can create difficulties in communication; when things go extreme, people in the same town are not able to understand each other.
But it is crucial that we protect and reserve the diversity in spoken Chinese, because these dialects are the vehicles of the very unique local culture and art forms. Huangmei Opera黄梅戏(huáng méi xì), one of the five major Chinese opera forms, was designated as Chinese National Intangible Culture Heritage in 2006. It is a form of rural folksong and dance and performed in Hui dialect. Pingtan评弹(píng tán), popular in southern Jiangsu, northern Zhejiang, and Shanghai, an art form of "story telling, joke cracking, music playing and aria singing", is performed in Wu dialect. The Chinese dialect is a highly comprehensive topic.
What I did here is just a brief introduction. My suggestion is that you can start with Mandarin which gives you access to most of China and many excellent works by Chinese writers and artists. When your mastery of Chinese increases, you may find more confidence to explore other dialects and cultures. No matter which way you choose, China, traditional and modern, reserved and open, is a fascinating country and it is worth your effort. Good luck with the journey! 下次再见啦！
Index Variety of Chinese
http://en.wikipedia.org/wiki/Varieties_of_Chinese#CITEREFLewisSimonsFennig2013 林林总总的汉语方言http://www.mifang.org/bk/e0/p05.html Classical Chinese
http://en.wikipedia.org/wiki/Classical_Chinese Written Vernacular Chinese
http://en.wikipedia.org/wiki/Written_vernacular_Chinese Huaxia http://en.wikipedia.org/wiki/Huaxia Wu-Chinese
http://baike.baidu.com/view/1711.htm Cantonese Phonology
http://en.wikipedia.org/wiki/Cantonese_phonology#Tones Chinese Phonology http://en.wikipedia.org/wiki/Standard_Chinese_phonology#Tonal_categories Mandarin vs. Chinese
http://www.chinese-lessons.com/cantonese/difficulty.htm Chinese Phonetics http://ccl.pku.edu.cn/doubtfire/Course/Modern%20Chinese/1_phonetics/Chapter_05_phonetics_initial%20final%20sound.pdf