For decades, Billboard Magazine has served as one of the music industry's most trusted barometers, measuring the popularity of songs and albums not only across the United States but around the globe.

Back on March 25, 1939, the magazine rolled out something new: a Hillbilly Hits Music Chart, designed to monitor the rising wave of hillbilly music. While the name might draw a chuckle today, what we now call country music was once widely referred to as hillbilly music.

At the time, hillbilly music was far from a mainstream genre. Still, the very fact that Billboard Magazine began tracking it spoke volumes about its growing appeal. As the genre's audience expanded, hillbilly music gradually became known as country music — and Billboard Magazine's Hillbilly Music Chart evolved right along with it, eventually becoming the Country Music Chart.

Over the course of the twentieth century, country music saw a remarkable rise in popularity. What had once been closely tied to rural and southern culture eventually transcended those roots, capturing listeners across the entire nation.

Today, Billboard maintains several country music charts to reflect the genre's many dimensions. These include the Hot Country Songs list for the overall most popular hits, the Country Airplay list for the top radio hits, the Country Digital Songs list for digital hits, and the Country Streaming Songs list for the streaming country hits. It's safe to say that hillbilly music has come an extraordinarily long way over the course of the last century.