1. Literature review: This is a research method to understand your research topic by analyzing the existing research and literature. This method can help you determine your research problems and how your research will fill the existing knowledge gaps.

2. Empirical research: This is a data-based research method, which answers research questions by collecting and analyzing data. This method is usually used in social science, natural science and other fields.

3. Qualitative research: This is a research method based on non-numerical data, through interviews, observation and literature analysis to understand the research issues. This method is usually used in humanities, social sciences and other fields.

4. Quantitative research: This is a research method based on numerical data, through statistical analysis and mathematical modeling to understand the research problems. This method is usually used in natural science, social science and other fields.

5. Case study: This is a research method based on specific individuals or events. Through in-depth study of specific individuals or events, we can understand their characteristics and influences. This method is usually used in social science, humanities and other fields.

6. Comparative research: This is a research method based on comparing different groups, phenomena or processes to understand their similarities and differences. This method is usually used in social science, natural science and other fields.

7. Experimental research: This is a research method to test hypotheses through manipulated variable, which can be used to verify theories or discover new knowledge and laws. This method is usually used in natural science, social science and other fields.

8. Modeling: This is a method to understand and predict phenomena by establishing mathematical models, which can be used to solve complex practical problems. This method is usually used in natural science, social science and other fields.