A hard bag inside the neck can be considered as enlarged lymph nodes, epidermoid cyst, thyroid nodule, carbuncle and so on. 1. Enlarged lymph nodes: Usually, a hard bag in the neck can be suspected to be enlarged lymph nodes, because the lymph nodes in the neck are rich, and the lymph nodes are the very important immune organs of the body, when there are infections in the head and face (upper respiratory tract infections, gingivitis, tonsillitis, etc.), systemic diseases (blood, tuberculosis), and tumors, etc., all of which can appear as enlarged lymph nodes in the neck. 2. Epidermoid cyst: If the hard bag is isolated intradermal or subcutaneous nodule, the size of several millimeters to several centimeters, there is white tofu dregs-like content after squeezing, and easy to secondary bacterial infection with redness, swelling, pus, ulceration, pain and other symptoms, it can be considered as epidermoid cyst. 3. Thyroid nodule: if the patient has a hard bag in front of the neck, it can be considered as thyroid nodule; most of the cases of this disease do not have any symptom, and some of them may have pain around the nodule, foreign body sensation in the throat, pressure sensation, etc.; the common causes of this disease include iodine deficiency, overgrowth of thyroid tissues, heredity, inflammation of the thyroid, thyroid cysts, and history of exposure to radioactivity. 4. Carbuncle: If this hard lump shows diffuse infiltrative hard lump and keeps increasing, with obvious local tenderness, multiple pus heads and pus and blood secretions, accompanied by tissue ulcers, even with symptoms such as elevated temperature and chills, it can be considered as carbuncle; this disease is usually caused by multiple adjacent hair follicles and surrounding tissues infected with Staphylococcus aureus. It is recommended that the patient consult a doctor in time, under the guidance of a professional doctor, carry out relevant examinations, clarify the cause of the disease, and then receive targeted treatment.