Trainspotting, in Wikipedia terms, is the general action of using primary or secondary sources to come to a non-synthetized, generally obvious, non-subjective but trivial conclusion. Typically, this will occur in any statistics-heavy topic or often in discussing the continuity of fictional, serial works, but are not limited to such areas. Examples can include:

  • Identifying which player on a baseball team had the most number of walks.
  • Stating that a reality show contest was the first of their race/gender to win the show
  • Noting that a certain prop in a television episode was previously used on an earlier one.

Trainspotting is not necessarily bad. However, they often lead to excessive trivia sections if not in check, a state inappropriate for an encyclopedia (other sites, like offsite wikis, or TV Tropes, are generally better suited for this information). Generally, including trainspotting conclusions in an article is not appropriate, but not disallowed. It is better to use sources to determine if such facts are appropriate for introduction. For example, a common solution for "Continuity" sections for serial television shows is to only include trainspotting facts that have been noted by other sources. Common sense and consensus should be used to identify when facts should be included. In some cases, such as for serialized fiction works, a statement of fact from earlier in the work's history may be built on in a critical manner for a later installment, though no otherwise direct reference is made to this earlier point. If it is impossible to describe the newer installment without referring to this older instance, it is appropriate to make that connection, ideally using citations to direct the reader to the older work.

The concept of trainspotting is based on the hobby of the same name, where railroad enthusiasts would spend time counting train engines and cars of certain types. Similarly, trainspotting on Wikipedia is doing similar accounting of a favored topic. Since there's a near infinite level of detail that could be added through this accounting, editors should strive to limit the inclusion of indiscriminate information generated from trainspotting.