Open Game License
The Open Game License (OGL) is one of the open content - licenses , that allows free recycling of its subordinate works . In this respect it is similar to the GPL and was also inspired by its idea of free software .
It was created by Wizards of the Coast (WotC) to facilitate the distribution of additional books for their role-playing game Dungeons & Dragons , especially to keep their set of rules present in areas that do not seem lucrative enough for WotC itself. The OGL is not to be confused with the d20 license , which allows the use of the d20 brand on one's own works.