This book details the characteristics of an ECG signal through the functionality and electrical activity of the human heart. This book provides a basic introduction and needs for developing implantable cardiac pacemaker systems. This book provides comprehensive details on ECG signal processing techniques that are useful for fast and accurate diagnosis of cardiovascular diseases. The book discusses the characteristics and parameters of a typical ECG signal and various noises that can corrupt an ECG signal. It also covers various challenges involved in different stages of signal acquisition, preprocessing, and detection of an ECG signal. The book also presents a detailed survey of various ECG signal detection and data compression techniques. The book contains detailed information on ECG signals and various noises that corrupt an ECG signal. It also includes de-noising techniques, ECG peak detection techniques, and ECG data compression techniques. It also includes step-by-step details to design various filters in MATLAB. This book, through detailed explanations, provides the reader with necessary information on ECG signal, ECG signal acquisition process, noise removal techniques, and the detection of ECG peaks.