Market research can be defined as a set of activities and approaches aimed at gathering information about companies as well as current and potential customers and their needs, possibilities, and expectations.
-- The Sage Encyclopedia of Educational Research, Measurement, and Evaluation
Primary market research includes the activities you undertake to get information from your (potential) customers or competitors (for example, interviews, surveys, focus groups, etc.).
Secondary market research includes third-party research on user groups or customers, relevant industries, and competitors.
This guide focuses on secondary market research sources. Consult our Primary Research for Business guide for resources to help you conduct your own market research.