Bernoulli's principle explains the lift of a frolf disc. As a disc moves through the air it cuts the air, creating two directions of airflow.  The airflow above the disc has a higher velocity than the air flowing beneath it because the rim minimizes the distance of airflow under the disc.  This difference in airflow also creates a difference in pressure.  Bernoulli’s Principle states that pressure will decrease as the velocity of airflow increases.  Adding to Bernoulli’s Principle is Newton’s 3^rd law.  As the air pushes up on the disc, the disc pushes down on the air, creating lift.