Just noticed that Groundbound asked about inverted spins.
An erect spin, which we're all used to, occurs when the directions of yaw and roll are the same. An inverted spin occurs when the yaw and roll are in opposite directions, and you generally enter it by applying full rudder and full forward stick when flying inverted at just below the -Ve g stall.
Inverted spins are thoroughly unpleasant and disorienting, but very few aircraft show any particular desire to enter one, and they will usually recover on control centralisation. However, as much as anything due to loads on the airframe and pilot (I recall an inverted spin in a Tincano where both I in the back and my pilot in the front went briefly into G-LOC when it recovered from -2½g into a 4g pull-out, not an experience I've any great desire to repeat) I wouldn't contemplate inverted spinning something that isn't cleared to do so.
G