This document provides an overview of research design topics including definitions, types of research design, and key concepts. It defines research design as a comprehensive plan or blueprint for conducting a research study. The main types of research design discussed are exploratory, causal, descriptive, and experimental. Exploratory research is aimed at formulating problems or hypotheses, while causal research seeks to determine cause-and-effect relationships. Descriptive research observes associations between variables, and experimental research tests hypotheses through manipulation of the independent variable. Key concepts explained include variables, hypotheses, experimental and control groups, and validity. The document also outlines the stages of developing a research design and merits of having a well-planned design.