This is an introductory book in cytology and general histology for the undergraduate for medical and Veterinary Medical students. This book will deal with cells and tissues from mammals and birds. This book is intended to give the students enough experience with the materials in a simple way so that, at the end of it they should be able to identify normal cells and tissues prepared by standard methods for light microscopy and to some extend the electron microscopy. We tried to make this course as easier as possible by using more drawings and illustrations either made by the author or by getting them from other sources as referenced at the end of this book. The new methodology of histology teaching encourages the combination of electronic course in association with the traditional teaching method to make the matter even more enjoyable and effective for 1st year veterinary students. Therefore, this book was introduced in association with an electronic course. The electronic course will provide a series of teaching materials and animations urgently needed for the undergraduate students to better understand this subject in more attractive way.