B.B. King

B.B. King on stage during the Thelonious Monk Institute of Jazz Honoring B.B. King event at the Kodak Theatre on Oct. 26, 2008 in Los Angeles, Calif.

Photo by Alexandra Wyman/Getty Images for Thelonious Monk Institute

Everyone knows why B.B. King sings the blues, but unless you know your way around a guitar, you probably don't know how he plays them. It all starts with something called the 12-bar blues. Almost all blues songs are written in this progressive scale, which mimics the call and response vocal tradition of African-American slaves in the Deep South.

­When W.C. Handy created the first certifiable blues hit, he used the 12-bar blues. Released to the public in 1914,­ "St. Louis Blues" was initially met with a lukewarm respons­e [source: Morgan]. By the 1930s, however, people all over the country could identify with the genre's theme, regardless of race. African-American artists such as Billie Holiday substantially changed popular culture and helped the blues become a permanent part of the American musical landscape. In the latter half of the 20th century, B.B. King pioneered the role of the lead guitar player and used the 12-bar blues in new and unique ways. He, along with other blues artists, helped transform the genre from an American movement into a global musical phenomenon.

­Today, the 12-bar blues is one of the most basic and essential chord progressions in any guitar player's repertoire. If you are a novice player, or would just like to freshen up on the basics, this instructional series from iVideosongs is a great place to start. You probably won't be ready to pen the next "The Thrill Is Gone" after watching, but learning this technique will undoubtedly help you become a better player.