HelpThing was written by members like you, with some help from LibraryThing staff.
View a list of all of the HelpThing topics.
The first rule of HelpThing is "be bold!" If you can add or edit it, go ahead. We also have a HelpThing Style Guide.
The tag mirror provides a tag cloud for your library, with a twist - it isn't based on the tags you put on your own books, but on the tags that other LibraryThing members applied to those same books. This allows you to see how other people categorize your library, as well as gave a way to get a quick sense of someone else's library, even if they didn't use tags.
Clicking on a tag will bring up a light box which shows the books in your catalog to which other people have applied that tag. The list includes the cover, title, author, number of times that tag is used for the book, and the prevalence index.
Tag Mirror was disabled for a time (starting in October 2007), but as of September 2008 it has now been redesigned and reactivated.