I want to know about this
If Hawaiian is a language from a small isolated island then how come it developed the same letter system as the west? The only possible explanation is that it is a modern language?
Aloha e @High-japan, to answer your question generally, written language has more or less been introduced from only a handful of sources. Example being many European and Arabic languages deriving from Phoenician which was developed from Egyptian Hieroglyphics. Also, how Japanese is derived from Ancient Chinese characters.
Hawaiian uses western letters because it was introduced from English & protestant missionaries from the Eastern United States. Before this, there is no known written form besides the use of symbolism.