What is "Shaka" ?

Fold your middle 3 fingers down, and keep your thumb and pinky straight up. There you've got a Shaka sign.
In Hawaii, shaka is one of those things that everybody just gets. You make a sign to say "thanks", "you're welcome", "sorry", "how'z it", "good bye", and even I love you! The sign is like the word Aloha itself, having many good meanings!  
There are many versions to the origin of the shaka sign. One version has it that a worker at the Kahuku Suger Mill (a stop at our Circle Island Oahu Driving Tour). It was said that Kalili Hamana, lost his middle 3 fingers due to an accident at the mill. Later Kalili worked at "the Hukilau" or what would later become the Polynesian Cultural Center. As Kalili stood greeting tourists and visitors, he would wave with his hand of only the thumb and pinky. Mistaking that he is having with a special sign, soon people started mimicing him by folding down their middle 3 fingers and waving to each other.  
Over the years, the sign was popularized by many people in the modern Hawaii society, politician running campaigns, news anchormen signing off, TV commercials and you name it.   
There you go, the origin of the Shaka sign!
When you are on a vacation in Hawaii, don't forget to throw out a Shaka sign to the car that yields to you, or the lady that says Aloha to you.

Kelly Slater, US Open2012, Surf Channel. Photo by Jason Alexander