Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. The ollie is a no-handed, aerial skateboarding trick, invented by Alan "Ollie" Gelfand in 1978, and refined by Rodney Mullen in 1982 to be performed on flat ground. When performing an ollie both the skateboarder and board leap into the air, remaining in contact throughout the jump. It is not intuitively obvious how the liftoff is achieved, making the trick visually striking. The ollie is a fundamental trick in skateboarding. As so many other tricks depend on it - for example the kickflip and heelflip - the ollie is often the first trick to be learned by a new skateboarder. The ollie typically takes considerable practice to learn. In skateboarding terminology, to 'pop' is to strike the tail of the skateboard against the ground, causing the board to rise into the air nose-first.