What does WAAS have to do with hunting gear? 

WAAS is an acronym for Wide Area Augmentation System but what exactly is a wide area augmentation system?  WAAS was developed by the FAA (Federal Aviation Administration) to improve the accuracy of the GPS (Global Positioning System).  The purpose of WAAS is to improve GPS enough to allow aircaft to use GPS in all phases of flight including the approach to airports.

So what does WAAS do?  WAAS uses a network of stations in North America and Hawaii that measure small variations in the GPS satellite signals.  These stations send the measurements to master stations.  The master stations generate correction messages and send them to WAAS satellites which then boadcast the messages back down to earth.  This is where your WAAS enabled GPS comes into the picture.  If your GPS is WAAS enabled, it recieves the correction messages from the WAAS satellites and uses them when it calculates your position.  The result is improved accuracy of the position fix you get from your GPS unit. 

There is a lot more information available about WAAS and related topics but hopefully this basic explaination will help give you the big picture on how a system developed for jumbo jets is helping hunters find that tree stand on a dark foggy morning.