Billy began the series as the stereotypical "nerd." The other Rangers, especially Trini, defended him loyally, but Billy later evolved to become a stronger individual. He was one of the top members of Angel Grove High's science club and often helped its younger members with their experiments. Billy's intelligence would help the Rangers save the world on many occasions,and he uses his intelligence to help others in need as well. Like his fellow rangers his true identity must be kept secret.