Tagging is a way of organising tiddlers into categories. For example, if you had tiddlers representing various individuals, you could tag them as ''friend'', ''family'', ''colleague'' etc to indicate these people's relationships to you.
* The coloured tag pills on a tiddler give you quick access to all the other tiddlers with the same tag, as well as to the tiddler that represents the tag itself.
* If a tiddler is serving as a tag, then the ''Tagging'' tab in its InfoPanel will show you which tiddlers are currently tagged with it.
* The ''More'' tab of the sidebar has a ''Tags'' tab that presents an overview of all your tags and lets you access all your tagged tiddlers.
* You can use [[filters|Filters]] to create lists of tiddlers based on their tags. You can then display any combination of the [[fields|TiddlerFields]] of those tiddlers. For example, you could build a glossary by listing the title and text of all tiddlers tagged ''Glossary''. Such lists can be formatted in any way you wish: e.g. bulleted, numbered or comma-separated.
* There are a number of special ''system tags'' that control the layout of tiddlers and the entire ~TiddlyWiki page. See [[Page and tiddler layout customisation]] for instructions.
You can use the [[tag manager|$:/TagManager]], found in the sidebar under ''More'' > ''Tags'', to change the colour of a tag's pill or add an icon to the pill.
* To change the colour, click the button in the ''Colour'' column to select from a colour picker. Alternatively, click the icon in the ''Info'' column, then type a [[CSS]] colour value in the ''Colour'' field
* To change the icon, click the {{$:/core/images/down-arrow}} button in the ''Icon'' column and choose from the list of available icons
By default, tagged tiddlers are listed in the order they were added to the wiki. The [[sort operator|Filter operator: sort]] can change the order to alphabetical.
If you want any other order, add a [[field called ''list''|ListField]] to the tag tiddler, and set its value to be a [[TiddlerChain]] of the tiddlers in that order.
# Start with the tiddlers in the ''list'' field, in the sequence given there.
# In each remaining tiddler, look for a ''list-before'' field. If this has a tiddler title as its value, insert the tiddler into the sequence just before that one. As a special case, if the field's value is blank, add the tiddler at the very start of the sequence.
# In each remaining tiddler, look for a ''list-after'' field. If this has a tiddler title as its value, insert the tiddler into the sequence just after that one.
# If any tiddlers still remain, add them to the very end of the sequence.