Poetry slam is conventionally defined as the art of competitive performance poetry. Invented in the 1980s by a Chicago construction worker named Marc Smith, slam is a fast-paced competition where poets have a limited amount of time to impress judges randomly selected from the audience. Performers use all the tricks of storytelling, songwriting, theatre, stand-up comedy, and cold hard poetry to wheedle points out of the judges from 0.0 (terrible) to 10.0 (perfect!).
Slam is not a passive performance; in addition to the judges, other audience members are strongly encouraged to participate by cheering, whistling, or mildly heckling the hosts or judges.