In my opinion, many club players do not fully appreciate the potential benefits of varying grips to help produce and deal with a robust arsenal of shots. The modern game of tennis has racket technology and court surfaces that allow for increasingly higher bounces and the player to impart more spin than ever before. With the higher bounces, ground stroke grips tend to be moving more western, which allows for a higher contact point further out in front than other grips, and more easily produces topspin.
If you take a look at the handle of a tennis racket, you will notice that rather than being rounded, there are eight bevels around the handle. By placing the knuckle of your index finger on different bevels, you change the angle of the racket face. The angle of the racket face significantly impacts the spin you can impart on the ball and the ideal contact point.
If you hold a racket by the head in front of you in your dominant hand with the handle pointing down with your fingers on the outside side of the strings and your thumb on the inside and then slide your hand down the handle, you will have the Continental Grip. For a right-handed player, this would be mean your index finger’s knuckle is on the second bevel going clockwise from the top (lefties are counterclockwise.). This grip is often called the “Hammer Grip” and is a classic and versatile grip. In the modern game, the Continental Grip is often used for serves/volleys/half-volleys/overheads/slice/drop shots, in fact, John McEnroe used it for every shot. In McEnroe’s days, the lower bounce allowed this to also be a viable grip for groundstrokes, but the groundstroke strike zone for Continental is very low and it is a difficult grip to produce topspin on groundstrokes with.
If you rotate one more bevel (righties clockwise, lefties counterclockwise) to the third bevel, this is the Eastern Forehand Grip, one more over to the fourth bevel is the Semi-Western Grip, and the fifth or bottom bevel would be the Western Grip and a full 135 degrees away from the Continental Grip. Basically, as you move away from a Continental Grip, the racquet face will close (begin to rotate forward) slightly making the contact point a little higher, a little further in front, and topspin a little easier. The Eastern forehand grip used to be the predominant grip in the low bouncing grass court days but is now a rarity in the modern professional game. Most players today have Semi-Western or Western forehands and play with a two-handed backhand. There are many combinations possible for the two-handed backhand, but oftentimes, the non-dominant hand will be in a Semi- or Full-Western Grip.
For those tennis purists who still hit a one-handed backhand the most common grip would be the Eastern Backhand Grip, which would have the base knuckle of your index finger on the first bevel, it is 180 degrees opposite the Western Grip, like the Western Grip, is the same for righties and lefties. The Continental Grip is great for serves and volleys because it is neutral, it can impart all types of spin on the serve and can be used seamlessly for the forehand and backhand volley where, oftentimes, there wouldn’t be enough time to switch grips anyway. The other bevels offer grips so extreme that their deficiencies outweigh their benefits and are not worth mentioning here. I would suggest playing around with grips particularly if you’re looking to add more spin or get more comfortable with higher or lower contact points. Using new grips may feel weird at first, but with patience, you will vastly improve.