The document discusses the history and development of pacemakers. In the past, there was no cure for sudden heart stoppage, which had a high mortality rate. To solve this problem, researchers created the pacemaker, a device that delivers electrical impulses to regulate the heartbeat. The pacemaker has evolved from early external pacers to implantable internal pacemakers, saving many lives and allowing patients to live more active lives. While pacemakers have advantages, their batteries require replacement through additional surgery.