This book will basically intends to provides necessary information about comets and its types with ancient history. This book contains a brief history of the development of cometary science in general. The basic information of comets, its structure, classification, designation and origin are discussed. The important role of comets in Solar System studies are then discussed. A brief description of cometary dust and different recent space missions are described. In writing this book, the author has freely consulted other books in the market and also the necessary link and references. I have tried my level best to provide necessary information about comet.