What was a tap-dancing challenge during the vaudeville era?

During the vaudeville era, the "challenge" was a prominent feature of a tap dancer's education and a common element in theatrical acts. In these intense "duels," tap dancers would compete against one another to demonstrate their skill, often performing furious, flying steps before attempting to top the moves of their opponent.1

These competitive exchanges, which also evolved from earlier "cutting contests" in the mid-to-late 1800s, served as an essential environment for dancers to mature by observing and incorporating each other's rhythmic innovations and techniques. One of the most notable exponents of this practice were the Four Step Brothers, who were renowned for their ability to execute these high-energy, competitive routines.12