The document outlines the differences between causal, exploratory, and descriptive research methods and why it makes sense to use secondary data before primary data. For section 1, it defines and compares the three research methods according to definition, format, purpose, data collection methods, and directionality of hypotheses. Exploratory research is informal and gathers preliminary information, descriptive research provides answers to questions like who and what, and causal research tests hypotheses about cause-and-effect relationships. Section 2 notes that secondary data is available at low cost but may not be timely, while primary data is proprietary but costly and time-consuming to collect. It concludes that secondary data is a good starting point to define research problems before collecting primary data.