The assignment content discusses various relationships between classes such as One-to-many, mandatory, and composition. The relationships are explained in the context of patient information, signs, recommendations, and a main window class. The main points include: the relationship between Patient_inforamtion and Signs classes is One-to-many and mandatory; Sign_Recommendation and Recommendation classes have a composition relationship because Sign_Recommendations cannot exist independently; and the Main window class serves as the starting point for the application, calling other classes or beginning the program.