Indexing anything is generally thought to be a royal pain in the butt. That’s because it is. But few would argue the basic utility of an index. With online search capabilities, of course, indexes are becoming passé, but they are still informative when you want an overview of what’s in a document or website.
With a WordPress blog, indexing can be as simple as imposing some logic on an existing list of categories — simple, that is, if you create a reasonably detailed list of categories as you go along. And don’t do what I did at one point and convert all your categories to tags. It can be done in WP with a single keystroke, but reversing the process requires tedious post-by-post editing. So Rule Number One is stick to categories. Tags are virtually useless by comparison.
Categories can, with some exceptions, be renamed, and they can be assigned parent categories, which creates a hierarchy of subcategories. Also, the number of categories appearing in a Category Cloud widget can be specified, and unwanted items can be blocked; maximum and minimum type sizes can also be designated. Tag clouds, on the other hand, have no controls. They show your top 40 tags, period; you have no control over the tags displayed or the type sizes used. Remember, too, that a tag cloud is the only way to display tags; there’s no drop-down tag or shortcode for tags. Nor can they be included in custom menus/nav bars; only categories and pages can be used there. Perhaps the only advantage to using tags is how quickly they can be added to a post, compared to deciding which categories to use and selecting those categories from a list. (Search engine spiders recognize both categories and tags, so that’s not a consideration.)
Establish your categories with the idea that they will form an index; then use the “Categories” widget without checking the “Show hierarchy” option. Voilà! Instant index.
If only I’d practiced what I’m preaching! My first mistake early on was converting my categories to tags before I fully understood the problems/limitations that imposed, so now, behind the scenes, I’m slowly converting all my tags back to categories. The hierarchy, which looks nice in a drop-down menu, alphabetizes the parent categories, and then the related subcategories under each parent category. If you choose not to show the hierarchy, all categories will be merged into a single alphabetized list with no parent-child distinction. For now I’ve decided this may be the more useful form, since readers won’t have to guess which parent category includes the item they’re seeking. (Maybe I’ll get some feedback on this.) As long as I keep categorizing instead of tagging, it’s easy to switch from one display to the other.
Obsessive-compulsive detail-oriented control freak neatnik types will find a lot of satisfaction in imposing order on their chaos. It’s an ongoing process for me because I keep rethinking (overthinking?) the best way to categorize a post: Is a post about tornadoes “Science,” “Technology,” or “Nature”? Aren’t “Economy” and “Business” almost the same thing? What, exactly, is the difference between “Science” and “Technology” and which would readers expect to see? How about the difference between “Nature” and “Environment”? Should a post about Libya be filed under “Middle East,” “North Africa,” “Greater Middle East,” or “MENA”? It’s seems there’s just no end to it. Maybe that’s why some people prefer tags. Ya think?