To start off, BASE jumping is an acronyme for Building Antenae (uninhabited tower) Span (bridge or arch) Earth. It is very similar to sky diving, however the is no plane. If you are to complete a BASE jump off of at least one of each of the four different genres covered in the acronyme BASE, you can apply for a BASE number. They are awarded sequentially starting with BASE-1 to the thousands.
The first BASE number was awarded to Phil Smith as BASE-1 in 1981.
