What is Gor?

Now, the simplest answer as to what Gor is is that it is also known as the Counter-Earth. A fictitious planet, which is supposed to be within the same orbit as Earth, but on the opposite side of the Sun.
Ruled by steel and concerned with honor, Gor is a barbaric world, where slavery is an ancient and universally accepted institution. Technologically advanced aliens, known as the Priest-Kings, who are the overseers of Gor, monitoring and protecting the planet. Over a period of thousands of years, the Priest-Kings have transported numerous people from Earth to Gor. Restricting the Goreans from using many forms of technology, even though they do excel within a few limited areas, where their technology even surpasses those of Earth. As an example, Gorean Physicians have created the Stabilization Serums, a cure for aging. Such a cure would be considered as priceless on Earth.
Now, on Gor, slavery is an ancient, historically developed institution. There are over hundreds of aspects and facets, with legal, social and aesthetic, it is very complexed. Slavery has its basis in the biological differences between men and women. Goreans has accepted slavery as a natural part of life, where male dominance is pervasive among mammals and universal among primates. There are few, who questioned its basic validity.
Within Gorean mythology, it provides a story, justifying the creation of slavery. It tells that long ago, there was a war between the men and women of Gor. That at the end, the women were defeated by the men. The Priest-Kings intervene, to prevent the men from killing all the women that they made the women beautiful. This was to entice the men of Gor to want to keep them instead of slaying them. But, as the price for their beauty, the Priest-Kings has decreed that the women of Gor would forever be the slaves of men. To serve and to please them.
Now, sometime in the past, there were a series of wars, loosely known as the Slave Wars. It went on and off, over a period of time, occurring among various cities within the middle latitudes. Even though the wars involved a large-scale slaving, there were other causes within conflict. Such as, the levying of tribute and the control of the trade routes. Thus, the wars developed most of the sanitation of slavery as a commodity, evolving the concern of slavery throughout the Merchant Law.
This brings the understanding of "What Gor is?" A brief overlook and out line of its history and people.