DemonRin wrote:Goku, Gohan, and Goten all have "Son" in front of their names because its their surname. It's their "Last" name so to speak. If their names were translated out to Western name order, it'd be "Goku Son" "Gohan Son" and "Goten Son".
Just to preempt anyone asking why people don't call him "Goku Son" in English, it should be pointed out that while it's typical in English to write the names of modern (ie post-Meiji Restoration) Japanese people in Western order, the names of pre-modern Japanese figures and modern people from other Asian countries such as China or Korea are still written in English with the surname first. For instance, in English you'll hear of Tokugawa Yoshinobu rather than "Yoshinobu Tokugawa", or Hu Jintao and Kim Jong-il rather than "Jintao Hu" or "Jong-il Kim" (it's also by no means universal for the names of even modern Japanese people to be written in Western order). Goku's namesake Sun Wukong is both ancient and Chinese, so naturally you don't see his name written "Wukong Sun". It makes sense to treat Goku's name the same way. Though is should be noted that at the end of the series, Goten is seen wearing a shirt that says "Goten Son".
I have no idea why the Son family are the only characters who are given surnames, but there you go.
Well, there's also the various characters from Penguin Village, and "Ten" might be Tenshinhan's surname, since Chaozu and the tournament announcer call him "Ten" ("Ten-san" or "Contestant Ten") and in the anime he says something about the Shishin no Ken being the secret technique of the Ten School of martial arts. There's also Mo Kekko, and maybe some other random people.
Videl does tell Gohan that it's rare these days for people to have surnames, so this is addressed in the series, if not actually explained.