O gauge refers to model train tracks whose rails are 1¼ inches apart. Even though O scale model trains frequently run on O gauge tracks, strictly speaking, the two Os have nothing to do with each other. The letter "O" is actually a misnomer since the designation was initially conceived to identify trains and tracks that were smaller in size than 1, which had been the standard. Since the only number smaller than 1 is 0, that’s how early O...Continue Reading