I. INTRODUCTION  
II. MEMORIZATION DEFINITION  
A. Memorization Definitions in Generalization Domain  
B. Memorization Definitions in Security Domain  
III. MEMORIZATION EVALUATIONS  
A. Example Memorization Evaluation  
C. Model Memorization Evaluation  
IV. MEMORIZATION IN DNN TRAINING  
A. Exploring Memorization Mechanism  
B. Memorization and Data Training  
C. Memorization and Repetition  
D. Memorization and Training Stage  
E. Memorization and Model Architecture  
F. Memorization and Overfitting  
G. Memorization and Data Augmentation, Regularization  
H. Memorization and Other Factors  
V. UNDERLYING RISKS OF MEMORIZATION LEARNING  
A. Memorization and Membership Inference Risks  
B. Memorization and Inversion/Extraction Risks  
C. Memorization and Poisoning Risks  
D. Memorization and Adversarial Risks  
E. Memorization and Differential Privacy  
F. Memorization and Other Risks  
VI. FORGETTING RESEARCH  
A. Forgetting Definition and Evaluation  
B. Forgetting Phenomenon  
VII. APPLICATION  
A. Noisy Label Learning  
B. Example Enhancement  
C. Privacy Audit and Protection  
D. Memorization Architecture  
E. Model Editing  
VIII. DISCUSSION AND FUTURE RESEARCH  
A. Memorization and Forgetting Mechanism  
B. Memorization and Forgetting for Training Discussion  
C. Memorization and Forgetting for Privacy and Security Discussion  
D. Application Discussion  
IX. CONCLUSION