Hey, I'm a little confused on the definition of a principle bundle. The basic question: "Do elements of the structure group, G, have to act on elements of the fiber, G, from the right?" I've read a bunch of papers that seem to imply that the fiber bundle structure group elements could act from the left and it's still called a principle bundle, but the wikipedia definition and a few others insist on the structure group elements acting on the right. What gives? I guess it's kind of nit picky, but I'd like to know what's going on here.