SERVES - hit before the ball bounces; used to start each point
- flat - hit without spin
topspin - hit by brushing up the back of the ball; usually has high trajectory and bounce.
twist - hit by brushing up and left-to-right; similar to topspin, but curves to the server's left, then kicks right.
slice - hit by brushing the right side of the ball; curves left in the air and on the bounce.
reverse slice - very rarely used; hit by brushing the left side of the ball.
underhand sidespin* - rarely used; hit by brushing underneath the ball from right to left; curves and bounces sharply right.
reverse underhand sidespin* - rarely used; hit by brushing underneath the ball from left to right; curves and bounces sharply left.
VOLLEYS - any shot hit before the ball bounces, but not with an overhead motion.
- drop - hit very softly, short, and with backspin.
stab - hit with an extreme stretching lunge, without much force.
drive - hit with a long forward swing, usually from farther back in the court.
swinging topspin - hit with a powerful topspin swing, usually from farther back in the court.
- backhand - hit on the player's backhand side.
squat - hit at a point of contact too low for full extension at the player's normal height, thus hit in a squatting position.
bounced - hit after the ball bounces.
Did I leave any out? Let me know at our tennis forum.

