This video includes descriptions for a few basic key terms that signal different aspects of the game:
Free ball: An emergency last contact for the opposing team that's sent over the net and is considered a "freebie" for your team. Free balls are an opportunity for your team to create a kill.
Down ball: An attack from the opposing team that's performed without a jump. In this scenario, blockers will rarely block as the ball is likely to be at a loopy trajectory.
First ball kill: When your team passes, sets and kills the ball and ends the point. Creating a team that can terminate plays is a critical part of game success.
Transition: When the ball is coming over and the front row hitters transition off the net in order to get in position to attack with a full approach.