Step 1 : Introduction to the question "What was the original name of cowboy Roy Rogers' horse, Trigger?"
...Roy Rogers' palomino horse, Trigger, was originally named Golden Cloud. He became "Trigger" after he began working in show business because he was often described as "quick on the trigger." This most famous horse in show business appeared in at least 80 feature films. Roy Rogers often joked that the horse commanded as much star power as the cowboy himself. Trigger's 20-year career included over 100 television episodes. Trigger even had his own comic book series. Source: AmericanCowboy.com