"Digit to Ride: How Sticking Your Thumb Out Became a Universal Gesture for Hitchhiking"

This article was really interesting to read and very informative. It told the history of the term "hitchhiking", and how the practice came into use, especially as it evolved over the years. The article was written in 2012 on slate.com, by Forrest Wickman, and it can be found here.