This book is about algorithm mapping, a design methodology that makes networks of algorithms in complex computer application systems visible and understandable. Although it is written from an IT point of view, it does not require any prerequisite knowledge about computer programming. The general public, as well as IT professionals, are invited. For the past thirty years in IT, nearly all of the requirements and documentation effort has focused on user interfaces such as web pages, but UIs are only the tip of the computer application iceberg. And some IT systems have no user interfaces at all. A vast amount of logic remains invisible below the surface. Algorithm mapping lets us understand what is happening behind the user interfaces, in a way that is equally meaningful to application developers, regulators, and the general public. Algorithm maps are the blueprints of algorithms. In his career in information technology, Douglas E. Wilson has variously been a software developer, consultant, and business analyst. He currently creates algorithm metadata and other software requirement specifications in the health care field. He guarantees that there is no AI generated content in this book. Doug lives with his wife Sally in Quincy, Massachusetts. His first printer was a typewriter.