There are many different methodologies used in various types of research and the term is usually considered to include...

quantitative methods, qualitative methods, mixed methods, experimental methods, observational methods, survey methods, case study methods, action research methods, ethnographic methods, phenomenological methods, grounded theory methods, historical methods, and content analysis methods.

a wide range of approaches, techniques, and strategies for conducting research. Here are some of the most commonly used methodologies in research:

1. Experimental Methodology: This methodology involves the systematic manipulation of variables to establish cause-and-effect relationships. It often involves random assignment of participants to different experimental conditions and control groups.

2. Survey Methodology: This methodology involves collecting data from a sample of individuals through the use of questionnaires or interviews. It is commonly used to study attitudes, beliefs, opinions, and behaviors of a population.

3. Observational Methodology: This methodology involves observing and documenting behaviors, events, or phenomena without intervening or manipulating variables. It can be done through direct observations or by using tools such as video cameras or audio recorders.

4. Case Study Methodology: This methodology involves in-depth investigations of a single individual, group, organization, or phenomenon. It often utilizes multiple sources of data, such as interviews, observations, and documents, to provide a holistic understanding of the subject under study.

5. Content Analysis: This methodology involves systematically analyzing and interpreting the content of various forms of communication, such as written text, audio recordings, or visual media. It is often used to study patterns, themes, or trends within a specific context.

6. Action Research: This methodology involves conducting research in collaboration with practitioners or stakeholders to address practical problems and improve practices or interventions. It is often characterized by a cyclical process of planning, implementing, reflecting, and revising.

7. Qualitative Methodology: This methodology explores subjective experiences, meanings, and interpretations of individuals or groups. Common techniques include interviews, focus groups, and analyzing textual or visual data.

8. Quantitative Methodology: This methodology focuses on numerical data and statistical analysis. It often involves collecting structured data through surveys or experiments and using statistical techniques to analyze and interpret the results.

These are just some examples of research methodologies, and researchers often adapt and combine different approaches depending on their research questions, objectives, and constraints.