The man in the photo is playing a vibraphone. Do you know what that is?
 

A vibraphone is a jazz instrument that was invented around 1920. It's a percussion instrument, so a musician must beat or strike it to make sounds. It looks a little like a xylophone and has tuned metal bars that a player hits with felt or wool beaters. Striking the bars makes a soft, mellow sound. Underneath the bars are "resonators," which add vibration to the sounds that are made. In addition, small electric fans between the bars and the resonators cause a vibrato, or trembling effect. These fans are what give the instrument its name.
 

Thousands of people can listen to a vibraphone as they enjoy jazz music every summer at the Joslyn Art Museum in Omaha, Nebraska. Jazz was invented by African American musicians in New Orleans, Louisiana, and Kansas City, Missouri, and other cities in the late 19th and early 20th centuries. What makes it different from other music is something called improvisation.

Usually a composer writes music and a musician plays it exactly as it was written. With jazz, the musicians start with a song but then improvise, or start making music up as they go along. That is why many jazz songs never sound the same way twice.