This application is a concise summary of the pathologic findings for hematologic malignancies. The typical features of each disease are listed with specimen recommendations for making a proper diagnosis. It must be noted that these features are those most commonly observed, and each may not be present in any given case. A diagnosis often requires the best fit for clinical and pathologic findings. Nevertheless, some diseases have required features for a diagnosis. When present, these essential elements are highlighted. In addition, some diseases have relevant comments. Finally, most diseases have an accompanying pathologic image for enhanced understanding. This application is intended to provide more practical and accessible information to medical personnel, but it should not be the sole source for diagnostic criteria. Consultation with the appropriate classification system is necessary. This application is a valuable resource for physicians, nurses, and medical students.