If you've ever seen a horse race, you know that those riders in the colorful outfits that ride the horses are called "jockeys." But did you know that not all jockeys ride horses? It's true!

Today's Wonder of the Day is all about those jockeys known more commonly as "disc jockeys" or "DJs." A disc jockey is simply someone who picks and plays recorded music for an audience.

Have you ever chosen and played songs at a birthday party? If so, you're a DJ!

The term “disc jockey" can be traced all the way back to 1935. Commentator Walter Winchell first used the term to describe radio announcer Martin Block.

Block became a star personality with his radio show called Make Believe Ballroom. In-between news announcements, Block would play recorded music, but he pretended that he was broadcasting from a ballroom with the nation's top bands performing live.

Combining the terms “disc" (referring to the old disc-shaped phonograph records) and “jockey" (a general term referring to any operator of a machine), Winchell came up with “disc jockey." The term has stuck ever since.

Block wasn't the first DJ, though. That honor goes to Ray Newby of Stockton, California. In 1909, 16-year-old Newby began to play records over a small transmitter while he was a student at Herrold College of Engineering and Wireless.

Today, there are many different types of disc jockeys. There are still plenty of radio DJs who play music via AM, FM, satellite and Internet radio stations. But there are also club, hip hop and mobile DJs who play music in nightclubs and dance halls or at all sorts of parties and events.

Today's DJs might still spin “discs," but the times have changed over the years. Phonograph records gave way to reel-to-reel tapes, then eight-track cartridges, then cassettes and compact discs. The modern DJ most likely plays digital music via an MP3 player or a laptop computer!

Modern DJs often use lots of equipment during their musical presentations. In addition to their favorite songs, they also use computers, amplifiers, speakers, headphones, microphones and special electronic mixing devices.

Many musicians write, record and perform their own music. Today's DJs have made playing others' music — and often remixing it with other songs or their own sound effects — an art form of its own.

Wonder What's Next?

Do you like water? We hope so, because tomorrow’s Wonder of the Day will feel just like HOMES!