Ireland Information Guide offers three ways to create groupings of articles. Each has its own advantages and disadvantages, and each is appropriate in different circumstances.
Categories should be on major topics that are likely to be useful to someone reading the article.
If the answer to either of these questions is no, then a category is probably inappropriate.
An article will often be in several categories. Restraint should be used, however — categories become less effective the more there are on a given article.
An article should not be in both a category and its subcategory, e.g. Microsoft Office is in Category:Microsoft software, so should not also be in Category:Software. An exception would be an article that defines a category, and so is itself a parent article of subtopics as well as one in a series of like topics — for instance, placing Ohio in both Category:U.S. states and Category:Ohio.
Categories appear without annotations, so be careful of NPOV when creating or filling categories. Unless it is self-evident and uncontroversial that something belongs in a category, it should not be put into a category.
An exception to the above rules is categories such as Category:Stub that are intended to aid the function of Ireland Information Guide editing.
Every category should be a subcategory of some other category. If you need to start browsing from the top of the category hierarchy, see Category:Fundamental. If you think a good parent probably exists but you just can't find it, add your new category to Category:Orphaned categories.
You should only use an article series box for an actual series — when it forms a complete linear series. Examples include presidents of the United States, movies in the Friday the 13th Series, or Narnia books. A series should have a natural ordering, whether chronological or otherwise. Alphabetical order is not preferable, as categories naturally arrange articles alphabetically, making a series box redundant, but sometimes they are used for small and verifiably complete sets, such as states in the United States. A category should be used instead where appropriate.
As with categories, all the articles in a box should substantially deal with the subject of the box.
If the answer to any of these questions is no, a box might not be appropriate.
For very long series, it is preferable to use boxes like those found at the bottom of Margaret Thatcher which only show the elements of the series immediately preceding and succeeding the article. For shorter series, however, the Template namespace may be employed to create a single box with all elements of the series.
The policy on lists is generally fairly permissive. While they need to meet the same standards of noteworthiness of any other Ireland Information Guide article, these standards are, as always, fairly lax. Thus, if you want to create a grouping of articles that does not meet the criteria for a category or a series box, a list is an excellent choice.
Lists also have a substantial advantage over categories and series boxes in that they can be annotated. A list can include items that do not yet have an article. It is also possible to apply the Related changes feature to a list, which does not work for a category.