One of the ways to treat cancer is chemotherapy. Chemotherapy is the treatment of cancer using anti-cancer drugs. The aim is to kill cancer cells while doing the least possible damage to normal cells. There is a variety of drugs available each of which or a combination of some lead to treat specific cancer disease. The purpose of this series of collection is to give information on the chemical structures, mechanism of actions of anti-cancer drugs which are in use. Additionally, some information on possible side effects which might occur during the treatment using such drugs is also provided.