1. Introduction  
2. Fairness in LLMs  
2.2. Defining Bias and Fairness in LLMs  
3. Evaluation Metrics  
3.1. Intrinsic Bias Evaluation Metrics  
3.2. Extrinsic Bias Evaluation Metrics  
4. Intrinsic Debiasing  
4.1. Pre-processing  
4.2. In-processing  
4.3. Post-processing  
5. Extrinsic Debiasing  
5.1. Data-centric Debiasing  
5.2. Model-centric Debiasing  
6. Fairness of Large-sized LLMs  
6.1. Evaluating Fairness of Large-sized LLMs  
6.2. What are the Reasons for Model Bias?  
6.3. Debiasing Large-sized LLMs  
7. Discussions  
7.1. Unreliable Correlation between Intrinsic and Extrinsic Biases  
7.2. Accurately Evaluating Fairness of Large-sized LLMs  
7.3. Further Explore the Reasons for Bias  
7.4. Efficiently Debiasing Large-sized LLMs  
8. Conclusions