An epidermoid cyst is a common, benign growth that forms beneath the skin. It occurs when skin cells multiply and become trapped in a sac, leading to a small, round lump filled with a thick, yellowish substance called keratin. These cysts can appear anywhere on the body but are most often found on the face, neck, and trunk. Epidermoid cysts are usually painless and may not require treatment unless they become infected or cause discomfort. If necessary, a healthcare professional can remove them through a minor surgical procedure. They are not cancerous and typically do not pose any serious health risks.