Primary Research: This is research that is done by the author of the source you are using where that author conducted some method of research to gather new data that s/he then reports, analyzes and interprets in that source. Primary = original, first-hand; the author of the source generated the research data they are using.

Secondary Research: This is when an author of the source you are using gathers existing data, usually produced by someone else, and they then report, analyze or interpret that other person's data. Secondary = second-hand; the author of the source did not generate the research data s/he is using.