The finger immediately adjacent to the thumb is called the index finger, also known as the index finger. Normal people have five fingers on each hand, the thickest and shortest, the root and the other four fingers are not lined up together is called the thumb, the finger next to the thumb is called the index finger. In working life, the index finger is the most commonly used, the most flexible, and the most cooperative with the thumb, digging, dipping, fishing for something to eat or taste, pointing direction and so on generally give priority to the use of the index finger, so it is called the index finger or show finger. In the “Hand Function Judging Standard”, there are provisions, such as hand structure integrity function for 100%, the thumb accounts for 40%, the index finger and the middle finger each accounts for 20%, the ring finger and the little finger each accounts for 10%. The hand and fingers are important functional organs of the human body, so it is important to pay attention to their protection in work and life, and to seek timely medical treatment in case of accidents or diseases.