It mainly includes general anesthesia, local anesthesia and compound anesthesia. They are also divided into inhalation, intravenous and basic anesthesia according to the route of entry of anesthetics into the body. Basic anesthesia is the intramuscular injection of certain general anesthetics (commonly used are sodium thiopental and ketamine) to put the patient to sleep and then perform anesthesia for surgery. Local anesthesia is the use of local anesthetics such as procaine and lidocaine to cause temporary loss of sensation in a particular area of the body. Commonly used methods include intradural anesthesia (block), nerve block, regional block, local infiltration anesthesia and surface anesthesia. 1.Intraspinal anesthesia is the injection of local anesthetics into the spinal canal through a spinal puncture, where the injection into the subarachnoid space is called subarachnoid block or lumbar anesthesia, and the injection into the epidural space is called epidural block. 2.Nerve block is the injection of local anesthetic into a nerve trunk (plexus) of the body to cause nociceptive conduction block in the area it innervates, commonly used nerve blocks are cervical plexus block, brachial plexus block. 3.Regional block is to inject local anesthetics around the surgical site to block the nerve endings in the surgical area and achieve the purpose of anesthesia. Local infiltration anesthesia is the injection of local anesthetic directly into the surgical site and evenly distributed to all layers of tissues in the entire surgical area to block the transmission of pain, which is a common anesthetic method for clinical minor surgery. 4.Surface anesthesia is the spraying or coating of local anesthetics with strong permeability on the surface of mucous membrane and conjunctiva to produce anesthetic effect. 5.Compound anesthesia is the simultaneous or sequential application of two or more anesthetics, auxiliary drugs (such as analgesics, tranquilizers, etc.) or anesthesia methods, so that they complement each other to enhance the anesthetic effect, protect patient safety, and meet the special requirements of certain surgeries. The choice of anesthesia should be based on the medical and surgical needs, indications and contraindications of the anesthesia method.