What is the primary difference between West's Key Number System and a West reporter?

The primary difference lies in the organizational structure of each system. West's Key Number System is specifically designed to categorize legal principles by topic, allowing researchers to easily locate relevant cases based on the legal issue they are exploring. This topical arrangement facilitates faster and more efficient legal research, as users can zero in on the specific area of the law relevant to their query.

In contrast, a West reporter compiles and publishes judicial opinions in a chronological order based on the date of the decision. This organization reflects the sequence in which the cases were decided rather than categorizing them by legal topic. Therefore, while the Key Number System enhances thematic research, the reporter provides a historical collection of case law, making the two systems serve distinct but complementary purposes in legal research.

The other choices mischaracterize either the Key Number System or the nature of reporters, such as suggesting alphabetical organization or limiting reporters to summaries, which do not accurately describe their functions.