1 INTRODUCTION  
1.1 Motivations  
1.2 Contributions of this survey  
1.3 Organization of the survey  

2 PRELIMINARIES  
2.1 Definitions of the symbols  
2.2 Definitions of the Machine Unlearning  

3 TAXONOMY, EVALUATION METRICS AND TARGETS OF THE MACHINE UNLEARNING  
3.1 Traditional unlearning taxonomy  
3.2 LLM unlearning taxonomy  

4 DATA-DRIVEN MACHINE UNLEARNING  

5 MODEL-BASED MACHINE UNLEARNING  

6 PARAMETER-TUNING LARGE LANGUAGE MODEL UNLEARNING  

7 PARAMETER-AGNOSTIC LARGE LANGUAGE MODEL UNLEARNING  

8 CHALLENGES AND THE FUTURE OF MACHINE UNLEARNING  

9 CONCLUSION