Who came up with the brilliant idea to swap the sensible polo for the Hawaiian shirt? Not all workplaces have such a strict dress code anymore. In recent decades, employees who are expected to dress professionally on a regular basis have had the opportunity to get a weekly reprieve from stuffy dress clothes. However, that wasn't the original reason behind the office tradition--there was a monetary incentive to do so, with the emergence of Aloha Friday.

Aloha Friday was the brainchild of Bill Foster, president of the Hawaii Fashion Guild. He came up with the idea to give two free shirts to each Hawaiian member of the House and the Senate with the hope that they would wear the shirts not only to stay cool in the summer, but also to give the company publicity. This plan was called Operation Liberation, and it began in 1966.

Hewlett-Packard came out with a similar idea at around the same time, but they claimed to have been emphasizing the importance of coming up with creative, out-of-the-box ideas, and their employees' ability to wear more comfortable clothing was just supposed to be the beginning of that process. This idea spread throughout southern California and, subsequently, all the way over to the east coast. After more and more offices started implementing this weekly tradition, it eventually became an excuse to wear unacceptable attire to work. Rick Miller, public relations representative for Dockers, saw an opportunity to promote the brand and put together a "Guide to Casual Business Wear" for HR representatives to distribute, giving their khaki pants a time to shine.

Nowadays, casual days are observed as a way to stay cool in the summer and warmer in the winter, becoming more of a cultural tradition than a way to increase clothing sales or promote creativity and free-thinking. Either way, white-collar workers everywhere still get the chance to loosen their ties and ditch the sensible shoes once a week.