Chopper refers to a particular type of motorcycle that was radically customized to meet the owner's design needs and desires, archetypical examples of which are the Harley-Davidsons as seen in the 1969 movie Easy Rider.

In the United States post WWII era motorcycle enthusiasts coming home from the war started to remove all parts which were deemed too big, too heavy, too ugly and/or not absolutely essential to the basic functionality of the machine. Typical elements fitting these criteria would be fenders, turn indicators, and even front brakes. As well, almost certainly the large, spring-suspended saddle was removed in order to sit as low as possible on the motorcycle's frame. These machines were modified to lose weight for dirt track racing advantages. (See the origin of the “Hell’s Angels” for more on dirt track racing)

James "Wild Child" Greene of the now world famous Wild Child's Custom Shop is heretofore recognized as the pioneer of the modern chopper design. Wild Child’s jumpstarted an American institution with its famous "It's a What?" magazine debut marking the beginning of an era at the same time as other friends later becoming "kustom kulture" celebraties of their own. Examples being, Sam/George Barris, Ed "Big Daddy" Roth, Ray Fharner and others of the era. Based out of Kansas City, Missouri Wild Child’s captured the imaginations of what‘s become five decades of prominent American motorcycle culture.