Bleomycin is a type of chemotherapy drug used in the treatment of various cancers. It belongs to a class of medications known as antineoplastic antibiotics, which are derived from the bacterium Streptomyces verticillus. Bleomycin is primarily used to treat cancers such as Hodgkin's lymphoma, non-Hodgkin's lymphoma, testicular cancer, and certain types of head and neck cancers.