You can make it jump up, stay low, skid or curve. Just as Gregg Maddux uses ball rotation to pitch a winning baseball game, you can use ball spin to change the rhythm and pace of a match to you r own advantage. For low balls, high balls, approaching the net or just a change of pace. Hitting slice requires slowly striking the middle to lower half of the ball from high to low, creating backspin. This spin allows the ball to sail off your racquet strings without going long.
Slice requires taking a short back swing and a long follow through.
It comes in handy when you're trapped by the ball and lack preparation time. The racquet face is only open to about a 10 to 15 degree angle. Beginners are inclined to strike the ball with a straight racquet face but opening slightly, whether on purpose or not will create this effective spin. Quickly brushing up the backside of the ball from low to high will make the ball spin forward, creating an ark that drives the ball down into the court. Topspin increases your margin of error and is essential for full-court battle.