Tiddlers can be assigned categories by assigning one or more tags. For example, tiddlers representing individuals might be tagged ''friend'', ''family'', ''colleague'' etc to indicate the relationship to the author.
Multiple tags can be applied to the same tiddler. Used effectively they provide a powerful way to explore content related to a tiddler.
TiddlyWiki offers several useful features based on the convention that a tag itself can be interpreted as the title of a tiddler.
! Using Tags
Tags are displayed at the top of the tiddler as coloured pills. Clicking on a tag pill drops down a menu showing links to all the tiddlers that carry that tag, along with a link to the tiddler representing the tag itself.
When editing a tiddler, the tags pills have a small ''x'' icon that allows them to be removed individually. There is also a text box to type the name of a new tag to be added, and a dropdown autocomplete list that shows matching tags that are in use.
! Tag Manager
The tag manager is available via a button at the top of the sidebar tab "Tabs", or you can link directly to [[$:/TagManager]].
! Assigning Colours and Icons to Tag
The colour used to draw a tag pill is taken from the ''color'' field of the tiddler titled with the tag. The colour can be specified as any CSS value (more modern browsers show a colour picker for the ''color'' field).
An icon can be associated with a tag by placing the title of the tiddler containing the image into the ''icon'' field of the tiddler titled with the tag.