The two main branches of research methodology are qualitative and quantitative. Multiple approaches are contained within these two branches, and they can be used together or independently of each other to prove (or disprove) a hypothesis.
Qualitative research methods are used to gain insight into reasons and explanations for certain behaviors and patterns. Examples of employing qualitative research methods include focus groups, in-person interviews and questionnaires.
Quantitative research involves analyzing statistics and data sets to create facts. This method typically is very impersonal and quite structured, and it utilizes polls and surveys to compile data and draw conclusions from that data.