The main focus of the series, besides the nature of the competitions, stems from the contrasting personalities of Kenny and Spenny, which usually impact the way each approaches the competitions. Spenny almost always follows very strictly both the rules and his ethics. He not only follows the rules to the letter, but also what he perceives as the intention and spirit of the competition statement. Kenny's approach is typically more unorthodox; he is often willing to use any means necessary—including cheating—to win.

Source: Wikipedia.org