I was surprised, for this was the first time I had known that my father had been War Chieftain of the city, or that he was even now its supreme civil official, or, for that matter, that the city was named Ko-ro-ba, a now archaic expression for a village market. The Goreans have a habit of not revealing names easily. For themselves, particularly among the Lower Castes, they often have a real name and what is called a use name. Often only the closest relatives know the real name.
On the level of the First Knowledge, it is maintained that knowing the real name gives one power over a person, a capacity to use that name in spells and insidious magical practices. Perhaps something of the same sort lingers even on our native Earth, where the first name of a person is reserved for use by those who know him intimately and presumably wish him no harm. The second name, which would correspond to the use-name on Gor, is common property, a public sound not sacred or to be protected. At the level of the Second Knowledge, of course, the High Castes, at least in general, recognize the baseless superstition of the Lower Castes and use their own names comparatively freely, usually followed by the name of their city. For example, I would have given my name as Tarl Cabot of Ko-ro-ba, or, more simply, as Tarl of Ko-ro-ba. The Lower Castes, incidentally, commonly believe that the names of the High Castes are actually use-names and that the High Castes conceal the real names.
Tarnsman of Gor, pages 58 - 59

"May I ask your name?" she asked tactfully.
"I am Tarl."
"Is that a use-name?"
"No," I said, "it is my true name."
"Talena is my true name," she said. Of High Caste, it was natural that she was above the common superstitions connected with revealing one�s name.
Tarnsman of Gor, page 107

"I am Zosk," he said.
I wondered if it were a use-name, or his real name. Members of low castes often call themselves by a use-name, reserving the real name for intimates and friends, to protect it against capture by a sorcerer or worker of spells who might use it to do them harm. Somehow I sensed that Zosk was his real name.
Outlaw of Gor, page 30