Where your hand goes on the handle, and which grip goes with which shot. Three of them show up in a single rally of mine. This is my routine, about a year in; yours might look nothing like it.
Your handle isn't round. It has eight flat sides, called bevels. Hold the paddle with the edge pointing straight up and look at the butt cap: the top flat is bevel 1, and you count clockwise from there (lefties, count counterclockwise). Each grip is named for where the big knuckle at the base of your index finger lands.
Moving from continental to western, your hand turns further around the handle and the paddle face closes. A closed face brushes up the back of the ball, which is where topspin comes from. The trade is that the further you go, the harder it is to hit anything else.
| Grip | Good for | Costs you |
|---|---|---|
| Continental bevel 2 | Dinks, volleys, blocks, resets, backhands, overheads. Same face on both sides, so no switching. | Hard to hit topspin drives. |
| Eastern bevel 3 | The handshake. Forehand drives and easy topspin. | Backhand volleys need a switch. |
| Semi-western bevel 4 | More topspin, and attacking high forehands. | Low balls get harder; slower to switch out of. |
| Western bevel 5 | Maximum topspin: serves and big forehand put-aways. | Backhands and fast net exchanges. |
The serve: deep western. Palm nearly under the handle, brush up the back of the ball, topspin. The serve is the one shot where you get all the time you want to set your hand, so it gets the most extreme grip I've got.
The kitchen line: continental. Mostly so I can backhand the ball without changing anything. When the dinks speed up, there's no time to turn your hand, and continental doesn't ask you to.
A ball at my right shoulder in a hands battle: the paddle turns my hand. At the kitchen line I'm already in continental, so when a ball comes in just above the chicken wing, I let the momentum of the swing rotate the grip from there around to what I think is western. I don't plan it; the paddle just gets there.
Every grip other than your home grip is a trip. You go there for one shot, and then you come back before the next ball. After the serve, that means getting out of western before the return shows up. After a put-away, it means back to continental before the counter.