The served ball passes so close to the server that the receiver could not see it on the way back. Rallying Players alternate hits. The player who is hitting the ball must hit the ball before it bounces twice on the ground. If a player hits the other player with the ball, the rally is replayed. If a player touches the ball while it is the other player's turn to hit, the first player loses the rally.
Safety Always wear racquetball goggles when playing.
If you decide to get serious about the game, you'll find that all tournaments require them, so you may as well get used to them now.