Designed as a text for the undergraduate students of instrumentation, electrical, electronics and biomedical engineering, it covers the entire range of instruments and their measurement methods used in the medical field. The functions of the biomedical instruments and measurement methods are presented keeping in mind those students who have minimum required knowledge of human physiology. The purpose of this book is to review the principles of biomedical instrumentation and measurements employed in the hospital industry. Primary emphasis is laid on the method rather than micro level mechanism. This book serves two purposes: One is to explain the mechanism and functional details of human body, and the other is to explain how the biological signals of human body can be acquired and used in a successful manner.