A research question drives your search. It is something that you want to know about your topic; something you will explore and try to locate sources. The 5Ws, can help you transform your research topic into a research question: Who? What? When? Where? Why?
For example, using the 5Ws, the topic of teen pregnancy can be expanded into the research question "What are the most important factors that have influenced the decline of teenage pregnancies in U.S. in the past ten years?"
Who Teens
What Decline Pregnancy Rate
When Past Ten Years
Where U.S.
Why is not part of the research question but more of the motivating factor for your investigation.