I know that urlencode function can convert some special characters and also Chinese characters into %xxx form.
However, what I'd like to know more about is the encoding mechanism of this function.
For example, how is it known that "%2C" stands for the "," character? And for Chinese characters, it would become even more complicated! For instance, the encoded word for the Chinese character "我" is "%A7%DA". How could this be done?!
Also, is there any mapping table for the convertion that I could refer to?