What is a tag?

We’re pretty familiar with the idea of tags these days, but what are they really? On Twitter and Instagram, a tag is a short phrase that some people use to enhance the searchability of their tweet. Sometimes this is about an event (#Tagbowl2020!) or just a recent trend (#relatable). Tumblr’s tags can range from single words to long sentences which are used in part for searchability but also to make quiet comments on the post in question. The Archive of Our Own (AO3) also sees use of tags as comments but with a system of monitoring to ensure searchability. AO3 allows for users to tag their works as they please, while staff members carefully unify tags so that searching for “pure cinnamon roll” also yields results for works tagged “precious cinnamon roll” but still maintains the tag as written on the work. (AO3’s tag wrangling is pretty neat and we could write a lot more about it, but we’re here to tell you about us, not AO3.)

When we refer to tagging a book, what we are talking about is laying out the contents of the book in an easy to read but detailed list. This list is broken up into a series of keywords or key phrases, called tags, each of which should cover, in some respect, an aspect of the story. While Library catalogs tag the broadest and most central themes in a book, a novel contains a great number of elements relevant to the narrative. These catalogues were developed with non-fiction in mind, to classify and sort them by topic and make their - often straightforward - content searchable but they also tend to carry the limitations of their pre-digital origins. Libraries, bookstores, and online resources typically sort novels by genre first, but finding more detailed information can involve digging deeply.

One thing we are accounting for is spoilers. Since we don’t want to leave any parts of a book untagged, spoilers will be hidden unless clicked, so we don’t reveal plot twists or spoil endings for you. However, the search will be unaffected by spoiler tags: Whether you want to find or avoid works with gory murder, the betrayal of a loved one, or the reunion of a broken family, you can!

To develop consistent tagging conventions, we tagged several books collaboratively, sometimes using over 200 unique tags for a single book. To display this many tags legibly, we need to comprehensively sort and categorize them. Keep reading for how we use tag types for that.