This document discusses different research methodologies including survey research, correlation research, and causal-comparative research. It defines each type of research and provides examples. Survey research involves collecting data through methods like interviews, questionnaires, and observations in order to describe populations. Correlation research examines relationships between two variables. Causal-comparative research attempts to identify causes or consequences of existing differences between groups. The document outlines key aspects of each methodology such as study design, purposes, examples, and basic steps.