A fluid, air or pus filled pocket surrounded by a membrane is called a cyst. It can develop anywhere in the body. A cyst can be benign or cancerous but mostly are benign. There are many types of cysts according to their location. Epidermoid cyst: small, benign cysts, due to buildup of keratin under the skin, usually in face head, neck or back area and may become swollen, red and painful. Sebaceous cyst: seen in face, neck or torso region, large, benign and may become infected and increase in size. Cyst of breast: most cysts are benign, may grow in size and become infected, usually because of normal skin bacterial entry by a skin trauma. Ganglion: appears on tendons of joints example wrist, ankle and feet. May increase in size and become painful by putting pressure on tendons. Pilonidal cyst: cyst in cleft in buttocks, usually due to poor hygiene, puberty or friction of cloths, it can easily become infected. Chalazion: cyst of eyelid usually upper lid, develops usually because of blocked gland ducts and may even become infected. Mucous cyst: a fluid filled cyst that develops on lip due to blockage of glands. Brachial cyst: birth defect that a lump develops on the side of neck, it causes irritation or infection, it is seen as a lump at the side of the neck. A symptomatic cyst can be removed, incision and drainage done under antibiotics and anti-inflammatory cover.