pinying in Chinese equals to phonetic symbol in English. Pinyin is only a system to label the pronunciation of the Chinese character(s), but it cannot replace Chinese characters for the time being. Articles written completely in Pinyin are difficult to comprehend. Therefore, it is not an official writing style, but a reading aid for whose who can't understand Chinese characters

Pinyin (拼音 pīnyīn) literally means "join together sounds" (a better translation being "phoneticize") in Chinese. Cantonese also has a pinyin-type system called Penkyamp, whose name derives from the same word as pinyin, albeit articulated in the Cantonese dialect. generally speaking, we learn pinyin in our elementary school when 6-8 years old.

First of all, you have to understand something about Chinese languages. In China there are several languages and I think you know at least Mandarin and Catonese. But there are more. There's Wu, Xiang, Hakka, Min etc. However, all Chinese usually know their own dialect (e.g. Hakka) and learn the standard language (Mandarin) as well. The characters look the same though, so it might be tough to teach them the correct pronunciation. In order to overcome this difficulty the Chinese use pinyin in order to teach the correct pronunciation. To illustrate why I will show you "Hello" in Mandarin and Cantonese: 你好 (Mandarin) - ni3 hao3 (1 is a high flat tone, 2 is a rising tone, 3 is a falling and then rising tone and 4 is a falling tone. 0 is 'toneless') 你好 (Cantonese) - nei5 ho2 So in order for Cantonese people to understand how they have to pronounce 你好 in Mandarin, they need to know the pinyin. Pinyin can be used to input Mandarin on your computer as well. You just type ni3 hao3 or ni hao and it will convert the pinyin to the respective characters. Sometimes you instantly get the right characters, but sometimes you have to select them from a list. After a while it will feel pretty natural though. There are some other ways to input characters by typing the strokes or by actually drawing them with a tablet (or mouse if you don't care about RSI). Hope this helps. Good luck!

pinyin, as best i understand it, is a way of writing how Chinese words sound using the English alphabet but with tones added. each of the four symbols over a letter represents one of the four tones. i hope that answers your question.