der_kluge said:
1) Have you developed a detailed world creation for your world?
2) Do you know how everything came to be - the origins of all the races? Or do you care?
3) Do your players know this origin? How much of it do they know?
I numbered your questions for easier answerin'.
1). Not really, really detailed, no. But have I done a brief "this is how the setting got to be the way it is," yes absolutely.
2). All the races, no. Some of them, yes. My history's entire purpose is to provide plot hooks, though, not just to be background. If it seems important, or I can use it to propel adventures, or gradually reveal interesting secrets, then I'll write it up, otherwise I ignore it.
3). No, the players usually start off knowing very little. In fact, they are often spectacularly
misinformed about the true history of the setting, and one of the key plot devices I love to use is the gradual uncovering of the "true, secret" history of the world. Kinda like in the Call of Cthulhu game; people have the history that they accept and know; the real history of the world, but a key element of the setting is that all kinds of other weirdness was really going on, that most people don't know anything at all about.
That's often how my campaigns go.