Boils are bacterial infections of the skin and cysts are swellings of one, and secondly boils differ from cysts in cause, location, treatment and size. 1. A boil is caused by an infection of the follicles. A boil is formed when a single or multiple hair follicles become inflamed due to a bacterial infection of the skin, and is often caused by a secondary infection of Staphylococcus aureus. Cysts, on the other hand, are caused by trauma, chronic inflammation, or congenital factors. They usually do not have bacterial infections and have a cystic wall, which varies according to the cyst, and the contents of the cyst are also different. 2. Boils occur on the surface of the patient’s skin, while cysts are often found under the skin or inside the patient’s internal organs. 3. Patients with boils can take some anti-infective drugs (such as amoxicillin, cefaclor, etc.) for treatment, and can also use topical mupirocin cream for treatment, and after the formation of abscesses, they can be surgically incised and drained, with regular medication changes, while patients with cysts need to go to the hospital for surgical excision, and other treatments are ineffective. 4. Generally, boils are small in size and only increase in size when they merge into carbuncles, while cysts can be large or small in size. It is recommended that patients with such swellings should actively seek medical attention and follow the doctor’s instructions for treatment or observation.