If you have wondered about the distinction between Aloha Shirt and Hawaiian Shirt, a key part of the answer is Palaka. Before the first brightly colored and patterned Aloha Shirts were ever made, there were Palaka Shirts being worn by plantation workers and other laborers in Hawaii, as unclearly shown in this image linked from an interesting site arguing that Hawaii is not legally a state. The first (partially out of picture), second (dark hat, facing right), and fourth (bending over) workers appear to be wearing the distinctive dark blue and white plaid known as Palaka. The other two may be wearing white or natural shirts, or severely faded Palaka. [Click on the image for the full-size version.]
There were a garbled mish mash of reasons that got me interested in Aloha shirts, none of which should have made me interested in Palaka, but it seemed like wherever I read about the history of Aloha shirts, I would find discussion and pictures of Palaka, and eventually I wanted one of my own.
The heyday of Palaka was the late 1800s through the 1920s, but much more recently they have become a way for people with Hawaiian roots to subtlely distinguish themselves from those wearing Aloha shirts, in a quiet bit of oneupmanship.
I'm not Hawaiian, never been there, probably never will be. But I like the shirts.