This compendium is written to be read at nights, weekends, and holidays. It has been elaborated with the intention to demonstrate "What is Anatomic Pathology?" and to serve as educational material for pathology residents, pathologist assistants, practicing pathologists, medical students, and as an extension to the education of other health care professionals. For pathology residents and pathologist assistants, the intention is to introduce the foundations of knowledge in the discipline of anatomic pathology using medical history, something not particularly addressed in a training program. It assumes that the trainees are committed to become pathologists and pathologist assistants and, because of that, are ready to walk an extra mile to dive into the intricacies of their science. The extra effort pays off later. To medical students who are in the process of selecting a post-graduate education, it gives them a picture of what can be expected if they decide to follow pathology as their specialty. These pages will also be useful to practicing pathologists because it addresses questions about the "meaning" of our daily activities, questions that are not frequently asked. It also should be of interest to other health care professionals, such as oral pathologists and surgeons in particular. Curious readers can learn about what pathologists think and do.