The book "History of Science" is a systematic study of the progressive development of science throughout the ages. The book is tailor made-made text and is divided into seven chapters whose main purpose and objective is to provide intensive understanding of the phenomenon of science. Since it is a detailed study of the process of science from their earliest times in human societies to the present, this book becomes a must reading text for undergraduate students, graduate students and lecturers. Therefore, the book is appropriate for every form of academic pursuit in Kenya and elsewhere.