The book ""Application of Criminal Psychology in Different Types of Crime"" discusses how criminal psychologists examine criminals such as robbers, rapists, white-collar criminals, and identity thieves, especially their thoughts, intentions, and motives, reactions, emotions and feelings when individuals engage in these criminal acts. The purpose of this book is determining why an offender commits a crime, from the time the criminal decision was made to the time the person appeared in court. The book emphasizes that effective criminal psychologists will use their knowledge to help find and capture criminals, thus ensuring the world is safe for everyone. This book mentions that criminal psychology is a niche profession in the field of psychology, in which psychologists hold various positions, including working with law enforcers to determine the profile of people who may have committed a particular crime, and giving their opinion in court where they describe the mental state of the offender, or work directly with the captured offender to catch others in their criminal network. This book explains how criminal psychologists understand the inner mechanisms of the human mind and brain. And apply their accumulated knowledge and professional training to evaluate a person's mental and physical state by studying the person and talking with them.