The whiskers above a cat’s eyes serve to protect the eyes, similar to human eyelashes. The cat's whiskers can also measure distance, providing real-time feedback on the width of the distance. The most important function of a cat's whiskers is to sense external things. When external objects touch the whiskers, the nerves behind the whiskers can sense it, and the information is transmitted to the brain through the nerves. The brain then responds based on the information. Whiskers are quite a part of the cat's perception, equivalent to a sensor, reflecting information to the brain internally and sensing external information externally.

Whiskers can assist cats in catching prey and provide cats with the precise size, direction, and moving position of prey. Cats cannot see clearly prey that is as close as 30 centimeters in front of them. When cats capture prey, due to distance limitations, their eyes may not be able to keep up with the high-speed moving prey. At this time, the whiskers will act as a sensor and in a very short time , the cat's whiskers will first stick to the face backward, and then quickly move toward the middle, and capture prey information. Once the cat captures prey information, its whiskers will immediately close and its paws will follow to catch the prey.

A cat’s whiskers can also express mood. If a cat’s whiskers are relaxed and stretch naturally to both sides, it means that the cat is in a calm mood. If the beard protrudes forward, it means that it is excited and may have seen prey and is about to attack. If the whiskers are close to the cheeks, the cat is nervous or angry.