Most people think about research in large categories labeled with field of researcher or the course that requires a research project. For instance, you might refer to historical research, scientific research, textual research, or sociological research. They are not precise as to the way someone tackles a research problem. The following chart from Mary W. George lists some, but by no means all, of the common approaches to investigation used in research projects.
Source: George, M. W. (2008). The elements of library research : what every student needs to know. Princeton University Press.