Secondary sources are descriptions and analysis that explain legal concepts and provide citations to primary sources. You can further filter (narrow) your Secondary Sources results by facets such as Date or Publication Type.
Statutes are the written laws that are collected in codebooks such as the United States Code (U.S.C) or the North Dakota Century Code (N.D.C.C.) The Statutes results list is arranged by "relevance" - that is, what Westlaw thinks is the most relevant statute based on you search terms.
Once you've found the statute(s) that apply to your legal question, the Notes of Decisions, Citing References and Context & Analysis tabs provide links to other documents that cite that statute (i.e., court cases and secondary sources about that legal issue.)
Cases are the written opinions of appellate and lower court judges. The results list is again arranged by "relevance" and your search terms are highlighted in yellow.
Case headnotes summarize each discrete legal issue discussed in the case and are linked to where in the case you will find it.